text:
User talk:Marcussnow

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Good luck! --Panic (talk) 16:34, 10 December 2007 (UTC)

title: User talk:Marcussnow


text:
User talk:Ifa205

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Hello, and welcome to Wikibooks!

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Good luck! --Panic (talk) 16:34, 10 December 2007 (UTC)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: User talk:Ifa205


text:
User talk:Xiornik~enwikibooks

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Hello, and welcome to Wikibooks!

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Good luck! --Panic (talk) 16:34, 10 December 2007 (UTC)

Image:The Psychology of Emotions, Feelings and Thoughts.pdf
I've nominated this for speedy deletion since Wikibooks is not your personal webhost and we do not allow soapboxes. – Mike.lifeguard  | talk 22:48, 29 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Xiornik. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Xiornik~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:53, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 05:39, 19 April 2015 (UTC)

title: User talk:Xiornik~enwikibooks


text:
User talk:Zekus

Welcome message
Hello, and welcome to Wikibooks!

Here are some tips to help you get started:
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 * Wikibooks is a collection of open-source textbooks. (What is Wikibooks).
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 * If you want to base your work here on materials from Wikipedia, please use WB:RFI (requests for importation) to bring the material over in compliance with the GFDL.
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You will find more resources in Community Portal. If you want to ask a question, visit the Study help desk, the Reading Room, IRC channel or ask me personally on my talk page. For site news, see the Bulletin board. It might be a good idea to add that page to your "watchlist" so that you can see when any new information is posted there. You can do that by clicking the tab labeled "watch" at the top of the page.

Good luck! --Panic (talk) 16:34, 10 December 2007 (UTC)

title: User talk:Zekus


text:
Talk:Chess/Optional homework/Solutions

Homework 2, Problem 1
Ruy Lopez Exchange variation http://en.wikibooks.org/wiki/Opening_theory_in_chess/1._e4/1...e5/2._Nf3/2...Nc6/3._Bb5/3...a6/4._Bxc6/4...dxc6/5._Nxe5

title: Talk:Chess/Optional homework/Solutions


text:
Wikijunior talk:South America/Uruguay

LOS INVITO A CONOCER http://solidario-contraelmaltratoinfantil.blogspot.com/. ALLI SE EXPRESA ALGO SOBRE MI PAIS: URUGUAY Y ALGUNOS TEMAS PUNTUALES SOBRE LOS DERECHOS DE LOS NIÑOS.-

title: Wikijunior talk:South America/Uruguay


text:
Wikijunior:Languages/Cherokee

What writing system(s) does this language use?
Cherokee is written with symbols invented by Sequoyah in 1819. In his system, each symbol represents a collection of sounds, instead of one letter like in English.

 * Cherokee symbol examples: Ꮔ (nu), Ꭽ (ha) , Ꮭ (tla)

How many people speak this language?
In the whole world there are only about 15,000 to 22,000 people who can speak this language.

Where is this language spoken?
Cherokee is mostly spoken in the United States in the state of Oklahoma and also on the Cherokee Reservation in Great Smoky Mountains, North Carolina.

What is the history of this language?
Although Cherokee has been a spoken language for thousands of years, it was not written down until Sequoyah invented a system in 1819. Today there are newspaper articles and other things written in this language.

Who are some famous authors or poets in this language?
John Ross was a French writer who visited the Cherokees in 1621 to learn their language. They said he was the best student they trained. He wrote a book in the Cherokee language called Europa, intended to teach the Cherokee what life was like in Europe.

What are some basic words in this language that I can learn?
Hello ... ᎣᏏᏲ (O-si-yo)

OK ... Ꮀ Ꮹ (ho wa)

I love you ... ᎬᎨᏳᎢ (gve-ge-yu-hi)

What is this? ... (do-i-s-di-hi-na)

What time is it? ... (he-la-ya-a-hli-li)

Where do you live? ... (ha-dlv-hi-he-la)

How are you? ... (do hi tsu)

I am well ... (do hi quu)

And you? ... (ne he na ha)

Good morning  ... (o s da su na le i)

Good evening ... (o s da su he ye e)

Good night ... (o s da su no e)

title: Wikijunior:Languages/Cherokee


text:
User:CJMiller/monobook.js

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title: User:CJMiller/monobook.js


text:
Horticulture/Corylopsis

Corylopsis is a genus of nearly 30 species of shrubs in the witch hazel family, Hamamelidaceae, native to eastern Asia with the majority of species endemic in China but with some also in Japan, Korea, and the Himalaya.

Description
They grow to 2–6 m tall, and often with a crown wider than tall. The leaves are ovate with an acute apex and a serrated margin, 4–20 cm long and 3–15 cm broad. The flowers are produced in late winter in pendulous racemes 3–9 cm long with 5-30 flowers; each flower has five pale yellow petals, 4–9 mm long. The fruit is a dry capsule 10–12 mm long, containing two glossy black seeds.

Varieties

 * Selected species:Native to China unless otherwise indicated

Uses
They are often grown in gardens for their very early, yellow flowers. They do have weak branches though, which are often damaged by heavy snow loads. Corylopsis prefers to grow in semi-shade or shade, protected from strong winds. It grows best on humus-rich soils. The sweetly scented flowering branches keep well in a vase. Corylopsis also makes good bonsai plants, especially C. pauciflora.

title: Horticulture/Corylopsis


title: User:Whiteknight/categorize2.js


text:
Horticulture/Erythronium americanum

Erythronium americanum (Trout lily, Yellow trout lily) is a plant native to woodlands in Eastern North America.

Description
Trout lilies are low-growing, colonizing plants with simple, spotted leaves and basal yellow flowers on short stems. The foliage is ephemeral in midsummer, dying back fully by late summer.

Growing Conditions
Trout lilies grow best in deep, moist, but well drained soils in deciduous shade. The foliage emerges in late winter, followed by early spring flowers.

Uses
Among magic-users, the plant is known as Adder's tongue, American Adder's tongue, Serpent's tongue and Adder's mouth. It is used in healing magic. A practitioner soaks the plant in cold water and applies it to a wound or bruise until the spot grows warm, then buries the wet herb in muddy ground. The wound is believed to be cured by this procedure.

Among magic users, Adder's tongue is associated with the planet Venus and the feminine spirit.

Maintenance
This plant can be difficult in the garden, due to its slow growth and ephemeral nature. The roots are surprisingly deep as well, making transplanting difficult. They do not tolerate heavy foot traffic.

title: Horticulture/Erythronium americanum


text:
Talk:Robotics Kinematics and Dynamics

This wikibook is to become an online textbook on the kinematics and dynamics of robots, providing a more in-depth view than the more general Robotics wikibook. I'm starting it as a part of a sort of school project I'm in at the moment. It's supposed to start growing steadily within the next few days and weeks (and months, update), as I will gradually be adding content to it.

title: Talk:Robotics Kinematics and Dynamics


text:
User:Waqjan

Here I am, studying at university, thought I could contribute some of what I have learnt here. (Writing it up would be good revision too)

/Fluid Mechanics Draft/

title: User:Waqjan


text:
User:Waqjan/Fluid Mechanics Draft

Introduction
Fluid mechanics is the study of how fluids flow.

A fluid is simply a liquid or a gas, or more precisely, a substance that deforms continuously when subjected to a tangential or shear stress, however small the shear stress may be. This means that some materials, such as amorphous solids, colloidal suspensions and gelatinous materials, while not being completely liquids or gases, are fluids so the general theories of fluid mechanics can be applied to them. However, these substances are not commonly studied at introductory fluid mechanics.

Fluid mechanics is a subdivision of continuum mechanics. This means that fluids will be considered as being able to be infinitely divisible, and not as collections of atoms or molecules.

Fluid Properties
In addition to the properties like mass, velocity, and pressure usually considered in physical problems, the following are the basic properties of a fluid:

Density
The density of a fluid is defined as the mass per unit volume of the fluid.

$$ \rho = \frac {m}{V}\ $$

Viscosity
Viscosity (represented by μ) is a material property, unique to fluids, that measures the fluid's resistance to flow. Though this is a property of the fluid, its effect is understood only when the fluid is in motion. When different elements move with different velocities, then the each element tries to drag its neighboring elements along with it. Thus shear stress can be identified between fluid elements of different velocities.

The relationship between the shear stress and the velocity field was studied by Isaac Newton and he proposed that the shear stresses are directly proportional to the velocity gradient. $$\tau = \mu \frac{\partial u} {\partial y}$$

The constant of proportionality is called the coefficient of dynamic viscosity.

Another coefficient, known as the kinematic viscosity is defined as the ratio of dynamic viscosity and density. $$ \nu = \mu / \rho $$

Reynolds Number
There are several dimensionless parameters that are important in fluid dynamics. Reynolds number (after Osborne Reynolds, 1842-1912) is an important parameter in the study of fluid flows. Physically it is the ratio between inertial and viscous forces. The value of Reynolds number determines the kind of flow of the fluid.

$$ Re = \frac{\rho V L}{\mu} = \frac{VL}{\nu} $$

where ρ(rho) is the density, μ(mu) is the viscosity, V is the velocity of the flow, and L is the dimension representing length for the flow. Additionally, we define a parameter ν(nu) as the kinematic viscosity.

Low Re indicates creeping flow, medium Re is laminar flow, and high Re indicates turbulent flow.

Reynolds number can also be transformed to take account of different flow conditions. For example the reynolds number for flow within a pipe is expressed as

$$ Re=\frac{\rho u d}{\mu} $$

where u is the average fluid velocity within the pipe and d is the inside diameter of the pipe.

Application of dynamic forces (and the Reynolds number) to the real world: sky-diving, where friction forces equal the falling body's weight. (jjam)

Pathlines and Streamlines
The path which a fluid element traces out in space is called a pathline. For steady non fluctuating flows where a pathline is followed continuously by a number of fluid elements, the pathline is called streamline. A streamline is the imaginary line whose tangent gives the velocity of flow at all times if the flow is steady, however in an unsteady flow, the streamline is constantly changing and thus the tangent gives the velocity of an element at an instant of time. A common practice in analysis is taking some of the walls of a control volume to be along streamlines. Since there is no flow perpendicular to streamlines, only the flow across the other boundaries need be considered.

Hydrostatics
The pressure distribution in a fluid under gravity is given by the relation dp/dz = −ρg where dz is the change in the direction of the gravitational field (usually in the vertical direction). Note that it is quite straightforward to get the relations for arbitrary fields too, for instance, the pseudo field due to rotation.

The pressure in a fluid acts equally in all directions. When it comes in contact with a surface, the force due to pressure acts normal to the surface. The force on a small area dA is given by p dA where the force is in the direction normal to dA. The total force on the area A is given by the vector sum of all these infinitesimal forces.

Control Volume Analysis
A fluid dynamic system can be analysed using a control volume, which is an imaginary surface enclosing a volume of interest. The control volume can be fixed or moving, and it can be rigid or deformable. Thus, we will have to write the most general case of the laws of mechanics to deal with control volumes.

The first equation we can write is the conservation of mass over time. Consider a system where mass flow is given by dm/dt, where m is the mass of the system. We have,

$$ \dot m = \int_{CS} \rho \left(   \mathbf{V}\cdot\mathbf{n}  \right) dA $$

For steady flow, we have

$$ \int_{CS} \rho \left(   \mathbf{V}\cdot\mathbf{n}  \right) dA = 0 $$

And for incompressible flow, we have

$$ \int_{CS} \left(   \mathbf{V}\cdot\mathbf{n}  \right) dA = 0 $$

If we consider flow through a tube, we have, for steady flow,

$$ \rho_1A_1V_1 = \rho_2A_2V_2 $$

and for incompressible steady flow, A1V1 = A2V2.

Law of conservation of momentum as applied to a control volume states that

$$ \sum F = \frac{d}{dt} \left(   \int_{CV} \mathbf{V} \mathbf{\rho}  \right) + \int_{CS} \mathbf{V}\mathbf{\rho} \left(   \mathbf{V}\cdot\mathbf{n}  \right)dA $$

where V is the velocity vector and n is the unit vector normal to the control surface at that point.

Law of Conservation of Energy (First Law of Thermodynamics)

$$ \frac{d\mathbf{Q}}{dt} + \frac{d\mathbf{W}}{dt} = \frac{d}{dt} \left(   \int_{CV} e\mathbf{\rho}  \right) + \int_{CS} e\mathbf{\rho} \left(   \mathbf{V}\cdot\mathbf{n}  \right)dA $$

where e is the energy per unit mass.

Bernoulli's Equation
Bernoulli's equation considers frictionless flow along a streamline.

For steady, incompressible flow along a streamline, we have

$$ \frac{p}{\rho} + \frac{V^2}{2} + gz = constant $$

We see that Bernoulli's equation is just the law of conservation of energy without the heat transfer and work.

It may seem that Bernoulli's equation can only be applied in a very limited set of situations, as it requires ideal conditions. However, since the equation applies to streamlines, we can consider a streamline near the area of interest where it is satisfied, and it might still give good results, i.e., you don't need a control volume for the actual analysis (although one is used in the derivation of the equation).

Energy in terms of Head
Bernoulli's equation can be recast as

$$ \frac{p}{\rho g} + \frac{V^2}{2g} + z = constant $$

This constant can be called head of the water, and is a representation of the amount of work that can be extracted from it. For example, for water in a dam, at the inlet of the penstock, the pressure is high, but the velocity is low, while at the outlet, the pressure is low (atmospheric) while the velocity is high. The value of head calculated above remains constant (ignoring frictional losses).

Chapters

 * Chapter 1: Introduction and Foundations of Continuum Mechanics

 * Chapter 2: Vector/Tensor Algebra and Calculus

 * Chapter 3: Conservation Equations: Differential Balances and Control Volume Analysis

 * Chapter 4: Dimensional Analysis

 * Chapter 5: One Dimensional, Steady Flow

 * Chapter 6: Flow Fields with More than One Independant Variable

 * Chapter 7: Exact Solutions to Navier Stokes Equations: Special Conditions

 * Chapter 8: Incompresible Flow

 * Chapter 9: Compressible Flow

 * Chapter 10: Turbulent Flow

 * Chapter 11: Geophysical Fluid Dynamics

title: User:Waqjan/Fluid Mechanics Draft


text: User talk:72.236.192.234

title: User talk:72.236.192.234


text: User talk:209.198.84.222

title: User talk:209.198.84.222


text: User talk:82.243.239.195

title: User talk:82.243.239.195


text:
User talk:209.212.22.61

Webaware talk 22:57, 10 December 2007 (UTC)

title: User talk:209.212.22.61


text:
Fortran/complex types

Variables and data declarations must occur at the start of all Fortran program units before any executable statements. Variables may have a "kind" that specifies its size in memory. The kind parameter can have different meanings for each compiler or processor, so be sure to check what kinds are available to you in your compiler's documentation.

Declaration style
There are several ways to declare a variable. The modern Fortran style is to be verbose and explicit. The following example declares an real array with the a kind of 8 (on most compilers this means 8 bytes long, i.e. double precision). The  attribute is quite long to type out, but may be more concise when declaring multiple arrays on a single line. If only a single variable is to be declared then it may be more concise to specify the dimension with parentheses next to the identifier. Variables may also be initialized with an assignment. The  is optional for backwards compatibility with older versions of Fortran. The older style of declarations use a  to denote the kind of a variable. Furthermore, the kind may be omitted entirely to simply use the default kind for your compiler.

Integer
The integer data type stores signed integer values (i.e. ..., -3, -2, -1, 0, 1, 2, 3, ...). On most compilers, the default kind stores integers as short integers 4 bytes in size. Long integers are usually 8 bytes. The allowed attributes are: allocatable, intrinsic, public, asynchronous, optional, save, parameter, bind, pointer, target, dimension (dims), private, value, external, protected, volatile and intent (inout).

Logical
The logical data type stores boolean vales and can only contain values  or. The default logical kind for most compilers is 4, occupying 4 bytes. Therefore, logicals are much like integers in terms of memory, but integers and logicals are generally not compatible for most operations. The allowed attributes are: allocatable, intrinsic, public, asynchronous, optional, save, parameter, bind, pointer, target, dimension (dims), private, value, external, protected, volatile, intent (inout).

Real
The real data type stores floating point data. Vales are stored in memory in scientific notation as a mantissa and an exponent. The default kind for real variables is 4, which consists of 4 bytes (32 bits). In this case 24 bits are used for the mantissa and 8 bits are used for the exponent. The allowed attributes are: allocatable, intrinsic, public, asynchronous, optional, save, parameter, bind, pointer, target, dimension (dims), private, value, external, protected, volatile, intent (inout).

All compilers support at least two kinds of real kinds for low precision and high precision numbers. But the standard does not specify what size these precisions should be. Most compilers use 32 bits for single precision and 64 bits for double precision. Therefore, many compilers support a  real data type that uses the higher precision that is available. However, for portablility it is much better to use the  intrinsic function to select the required kind parameter for your variables precision.

Complex
In mathematics, a complex number has a real and an imaginary component. Complex numbers in Fortran are stored in rectangular coordinates as a pair of real numbers (real part first, followed by the imaginary part). The default kind of complex numbers is always the same as the default kind of the real data type. So a complex variable of kind 4 will contain two reals of kind 4. If kind 4 reals corresponds to 4 bytes, then the default complex variables will be 8 bytes in size. The allowed attributes are: allocatable, intrinsic, public, asynchronous, optional, save, parameter, bind, pointer, target, dimension (dims), private, value, external, protected, volatile, intent (inout).

Complex operations
All of the arithmetic operators can take a complex number on either side. Fortran automatically handles complex arithmetic and the special rules of imaginary numbers.

Care must be taken in using function calls that might cause an error. For instance, taking the square root of the real number  will result in an error, because -1 is outside of the domain of real square root. Taking the square root of the complex number  is allowed because -1 is in the domain of complex square root.

Character
The character data type stores strings of characters. The default kind of character variables is usually 1 which represents ASCII characters. Kind 2 usually represents the ISO 10646 standard characters. Character variables are unique in that they also have a  parameter in addition to   which specifies the number of characters in the string. Typically a single character occupies 1 byte in memory. In addition to this, character data types can also be arrays. The old style declarations does not have a kind parameter and only has the length parameter.

Literal constants
Data embedded in expressions are referred to as literals or constants. Literals can have a particular data type depending on how they are written. For example, in the below line the value 1 is an integer. The below table demonstrate how to type literal constants. Note that the parentheses notation for complex numbers cannot be used with variables. For example,  is invalid. To convert real variables to complex, use the  function:

Any expression involving complex numbers and other numbers is promoted to complex.

Parameter constants
Constants literals are simply unnamed data. Variables can be constants too. They are declared with the  attribute. These variables are immutable and assigning to them after they have been declared will cause an error. They must be initialized with a value when they are declared.

title: Fortran/complex types


text:
User talk:BethH

Welcome message
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Good luck! --Panic (talk) 03:56, 11 December 2007 (UTC)

title: User talk:BethH


text:
User talk:Elwakeel20

Welcome message
Hello, and welcome to Wikibooks!

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Good luck! --Panic (talk) 03:56, 11 December 2007 (UTC)

title: User talk:Elwakeel20


text:
User talk:Waqjan

Welcome message
Hello, and welcome to Wikibooks!

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Good luck! --Panic (talk) 03:57, 11 December 2007 (UTC)

title: User talk:Waqjan


text:
User talk:Supermackin~enwikibooks

Welcome message
Hello, and welcome to Wikibooks!

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Good luck! --Panic (talk) 03:57, 11 December 2007 (UTC)

Control Systems
Hello Supermackin, welcome to wikibooks! I saw your edit to the Control Systems book, and I am glad: It's a good book that has been developing slowly because there are so few people with enough knowledge in the area to contribute to it. I'm an engineering graduate student myself, EE not Aerospace. Let me know if you need any help, or if you have any questions. Good luck, and happy editing! --Whiteknight (Page) (Talk) 13:29, 11 December 2007 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Supermackin. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Supermackin~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:44, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 05:34, 19 April 2015 (UTC)

title: User talk:Supermackin~enwikibooks


text:
User talk:NinjaSkitch

Welcome message
Hello, and welcome to Wikibooks!

Here are some tips to help you get started:
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 * Remember to conduct any editing experiments in the sandbox.
 * You can tell the community something about yourself in your userpage.
 * You can get to this page by clicking the tab at the top of the page labeled with your registered username.
 * Wikibooks is a collection of open-source textbooks. (What is Wikibooks).
 * If you are a Wikipedian, see Wikibooks for Wikipedians for a primer on how things work here (it's a little different).
 * If you want to base your work here on materials from Wikipedia, please use WB:RFI (requests for importation) to bring the material over in compliance with the GFDL.
 * If you're an instructor and plan on using Wikibooks for a class project, see Guidelines for class projects
 * Please say hello at the Reading Room with any questions or ideas.
 * Eventually, you might want to read the Manual of Style and Policies and Guidelines.
 * Help us by participating in policy and guideline creation.
 * Please take a look at Naming policy before starting a new book.
 * Remember to maintain a Neutral point of view.
 * Explore, be bold in editing pages, and have fun!

You will find more resources in Community Portal. If you want to ask a question, visit the Study help desk, the Reading Room, IRC channel or ask me personally on my talk page. For site news, see the Bulletin board. It might be a good idea to add that page to your "watchlist" so that you can see when any new information is posted there. You can do that by clicking the tab labeled "watch" at the top of the page.

Good luck! --Panic (talk) 03:57, 11 December 2007 (UTC)

title: User talk:NinjaSkitch


text:
User talk:Koreshky

Sorry for not welcoming you before that template message. You might find this info useful:

Come introduce yourself at the new users page. If you have any questions, you can ask there or contact me personally. – Mike.lifeguard  | talk 04:31, 11 December 2007 (UTC)

Copyright problem with Image:2496475710098511775S600x600Q85.jpg

 * Please take care to note specifically how this image is to be licensed using a license template. If you need help to decide what licensing option you want to use, ask on my talk page or at WB:HELP. Thanks; happy editing. – Mike.lifeguard  | talk 04:18, 11 December 2007 (UTC)
 * Thank you! – Mike.lifeguard  | talk 04:30, 11 December 2007 (UTC)

title: User talk:Koreshky


text:
Fortran/memory management

Introduction and historical background
Most Fortran programs prior to the Fortran90 standard used self-contained data, without structures, and without much in the way of shared, structured data. However, it was possible to share data, in structured and unstructured ways, using common blocks. Furthermore, there used to be little memory management going on in a Fortran program. Until Fortran90 allocated storage wasn't even possible, except via certain extensions (e.g. Cray pointers). Modern Fortran, however, supports many modern programming paradigms, has full support for allocatable data (including allocatable types), and allows for the use of pointers.

Shared variables in modules
Since Fortran90, shared variables are conveniently managed by the use of modules. Common blocks were used to define global memory prior to the Fortran90 standard; their use in modern Fortran is discouraged. A Fortran module can also contain subroutines and functions, but we shall leave the discussion of these features for later. As for the management of shared variables, they may be defined in a module: Note that it is considered good practice to declare any module private, even if it contains only public variables. Although  is the default for a variable in a module, meaning that it retains its previous value whenever the variables within the modules are used, it is sometimes considered good practice to make this explicit. The module can then be used in the main program:

Common blocks
Common blocks have been replaced by the use of public variables in modules in modern Fortran standards (Fortran90 and later). They are, however, historically important due to their use in older Fortran standards (77 and prior). A common block was Fortran's way of using shared, common storage for standards prior to Fortran90. In its simplest form, a common block is a way of defining global memory. Be careful, though. In most languages, each item in common memory is shared as a globally known name separately. In Fortran, however, the common block is a shared thing. I'll show several examples, but each example will share  and , and  , a 10x10 array of real numbers.

In C, for instance, I can define the shared memory using: and use these data elsewhere with: Note that one module declares the storage, and another uses the storage. Also note that the definitions and usages are not in the same order. This is because in C, as in most languages,,  , and   are all shared items. Not so in Fortran. In Fortran, all routines sharing this storage would have a definition something like this: This common block is stored as a block of data, as a linkable named structure. The only problem is that we don't know its name. Various compilers will give various names to this block. In some systems, the block actually doesn't have a name. We can avoid this problem by giving the structure a name. For instance, Using this form, two different Fortran programs can identify the same area of storage and share it, without having to know the structure of all shared storage. Also using this format, a C or other program could share the storage. For instance, a C program wanting to share this storage would declare the same storage as follows: In the above example, having the  names match is critical, as well as having the types, sizes, and order match. However, having the names internally match is not since these names are known only locally. Also note that in the above example, Fortran's  matches C's.

Byte alignment
Byte alignment of intrinsic data types can mostly be ensured simply by using the appropriate kind. Fortran does not have any way of automatically ensuring derived data types are byte aligned. However, it is quite simple for the programmer to ensure that appropriate padding for data is inserted. For example, let's say we have a derived type that contains a character and an integer Arrays of this type will have elements of size 5 bytes. If we want the elements of an array of this type to align every 8 bytes we need to add 3 more bytes of padding. We can do this by adding characters that serve no other purpose than as padding.

Memory management with pointers
In Fortran one can use pointers as some kind of alias for other data, e.g. such as a row in a matrix.

Pointer states
Each pointer is in one of the following states
 * undefined: right after definition if it has not been initialized
 * defined
 * null/not associated: not the alias of any data
 * associated: alias of some data.

The intrinsic function  distinguished between the second and third states.

Overview
We will use the following example: Let a pointer  be the alias of some real value.

For the next example we will use a real matrix  as target and the pointer   should alias a specific row.

Pointers can also be appointed to other pointers. This causes them to be an alias of the same data that the first pointer is. See the example below.

Ordinary vs. pointer assignments
The difference between ordinary and pointer assignments of pointers can be explained by the following equalities. Assume this setup

Ordinary assignments of pointers lead to assignments of the data they point to. One can see this by the following two statements which are equal.

In contrast, pointer assignments changes the alias of one of the pointers and no change on the underlying data. See the equal example statements.

Memory allocation
After definition of pointers one can allocate memory for it using the  command. The memory pointed to by a pointer is given free again by the  command. See the following example.

Allocatable vs. pointer
You can declare an array to have a known number of dimensions, but an unknown size using allocation: You can also declare something as a pointer: In archaic versions of FORTRAN (77 and before), you'd just have a big static array and use whatever portion of it you need.

title: Fortran/memory management


text:
User talk:Dprasen~enwikibooks

Come introduce yourself at the new users page. If you have any questions, you can ask there or contact me personally. – Mike.lifeguard  | talk 04:18, 11 December 2007 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Dprasen. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Dprasen~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:10, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 04:54, 19 April 2015 (UTC)

title: User talk:Dprasen~enwikibooks


text:
User talk:RedBeta1096

Come introduce yourself at the new users page. If you have any questions, you can ask there or contact me personally. – Mike.lifeguard  | talk 04:18, 11 December 2007 (UTC)

title: User talk:RedBeta1096


text:
Fortran/Mixing languages

Types
Fortran types map quite well to intrinsic types in other compiled languages. The following is a table of Fortran-to-C types:

Arrays
The layout of Fortran arrays in memory contrasts with arrays in C and many C-based languages. When iterating over contiguous array elements in C, the rightmost array subscript varies the fastest, while in Fortran, the leftmost array subscript varies the fastest. Hence the element following  in contiguous memory is , not. Furthermore, the element sub-scripting in C starts at 0, while Fortran starts at 1 by default. An element in Fortran may be, while the equivalent value in C code would be. However, when passing a Fortran array to a C function, you do not need to (and should not) reshape the array into C-style subscripts first; the compiler will automatically do this for you.

Global Storage
See the Common Blocks section.

Subroutine and function calls
Many languages push their arguments onto the stack, some as constants and some as addresses. In most compilers, Fortran will compile a block of pointers to variables and constants, and push the address of that block. So, if we had a Fortran procedure defined as follows: then the C definition would be: The C code could call the routine as follows:

The PL/1 Special Case
In PL/1, you can define an external common block, subroutine, or procedure to be of type FORTRAN. When you do this, everything, down to subscript order, will be handled for you. Likewise, you can define a PL/1 item, such as a subroutine, to be of type FORTRAN, and it will then be callable by Fortran using Fortran's calling conventions.

title: Fortran/Mixing languages


text:
User:NinjaSkitch

{| cellspacing="3"
 * - valign="top"
 * width="65%" style="border: 1px solid #000000; color: #000000; background-color: #EEEEEE"|

Introduction
Hello, world.

My name is Scott, and I'm here mainly to work on the following book:

Game Design and Programming

Game programming is my specialty, and I love helping other people learn. I know it's very tough to get started, because there aren't many good free resources for game development, but I hope in time this WikiBook will be the best resource available!

As for the book itself, I'm not sure how many folks are actively working on it, but I plan to take some heavy action on it before anyone decides to delete it. So, if you object to anything I do, please let me know!

 * width="35%" style="border: 1px solid #000000; color: #000000; background-color: #EEFFEE"|

About Me
{| WIDTH="100%"
 * style="background-color: #FFEEEE; border: solid 1px #000000; padding: 1em;" valign=top|

Interests

 * Cross-platform Game Programming
 * Game Engine design
 * Data abstraction for games
 * Fresh Networking ideas
 * Camera work!
 * This especially! Ever think that a game could have been so much better, if only the camera didn't suck? It is very difficult to get the camera to be in the right place at the right time, with many objects the user could want to focus on. I hope to bring some new and fresh camera ideas to games during my career.
 * }

{| WIDTH="100%"
 * style="background-color: #EEEEFF; border: solid 1px #000000; padding: 1em;" valign=top|

Currently Working On...

 * Game Design and Programming
 * }

 * }

title: User:NinjaSkitch


text:
User:Supermackin~enwikibooks

Supermackin is an Aerospace Engineering Graduate student at the University of Illinois.

title: User:Supermackin~enwikibooks


text:
User talk:128.208.76.146

Welcome!
Welcome to Wikibooks, a collection of open-content textbooks! You don't have to log in to read or edit articles on Wikibooks, but creating an account is quick, free and non-intrusive, requires no personal information, and gives you many benefits, including:
 * The use of a username of your choice
 * The ability to view all your contributions via a "My contributions" link
 * Your own user page
 * Your own talk page which, if you choose, also allows users to send you messages without knowing your e-mail address
 * The use of your own personal watchlist to which you can add articles that interest you
 * The ability to rename pages.
 * The ability to upload images
 * The ability to customize the appearance and behavior of the website
 * The eligibility to become an administrator
 * The right to be heard in votes and elections
 * Your IP address will no longer be visible to other users.

We hope that you choose to become a Wikibookian and create an account. Feel free to ask me any questions you may have on my talk page. By the way, make sure to sign your posts and comments with four tildes (~~~~), which will let others know who left it. --Panic (talk) 06:01, 11 December 2007 (UTC)

title: User talk:128.208.76.146


text:
Fortran/error handling

Typically in an error situation, your program will stop, and you'll get an error message. The only exception to this is that at the end of  and   statements' parenthesized control list, you can add,   to determine which line to jump to in the event of an error.

Modern Fortran (from Fortran 90 onwards) has introduced four main areas for error capture:

1) File handling and i/o operation error handling

2) IEEE floating point error detection and reporting

3) Dynamic allocation

4) Command line operations

File handling and I/O Operations
All the external file handling statements and I/O operations (, ,  ,  ,  ,  ,  ,  ,   and  ) can now take optional   and   clauses. is an integer which returns a non-zero value if there is an error, in which case, the character variable assigned to  will return a brief error message. The non-zero integers and the messages are compiler dependent but the intrinsic module,, gives access to two important values:   and. If an error occurs, and  is non-zero, execution will not stop. The ERR clause is still supported but should not be used.

Example
Note that the length required for the message character is vendor and error dependent.

IEEE floating point error detection and reporting
This is a big topic, but in essence modern Fortran provides access to three intrinsic modules:,   and. These features can be used to intercept errors such as divide by zero and overflow but at the expense of some performance.

The  module controls access to the features the programmer may require, by use association in the scoping unit where the programmer places the use statement,

Example
See Chapter 11 in Metcalf et al, Modern Fortran Explained, OUP. All the necessary basic facilities exist in order for the programmer to construct a try/catch system if desired.

Dynamic Allocation
Modern Fortran allows run-time allocation and deallocation of arrays of any type, and a typical error might be to try to dynamically allocate an array so large that there is not enough memory, or an attempt to deallocate an array which is not already allocated. There are optional clauses  and   which can be used to prevent program failure and allow the programmer to take evasive action.

Example
These features are available in the equivalent coarray features.

Command Line Operations
Modern Fortran also supports error detection for the execution of command line operations,

Example
In this example, the programmer of the my.exe program has the responsibility for what codes are returned and what error messages are exposed, except that -1 and -2 are reserved for allowing the compiler vendor indicating what features may be supported.

title: Fortran/error handling


text:
Template talk:Archive list long

A friendly reminder: we need to reduce the use of #ifexists to fewer than 100 per page. This page is transcluded in template:archive box. Hillgentleman (talk) 07:17, 11 December 2007 (UTC)
 * By my count, this has 36. 36<100, so this is ok, I think. Thanks for the reminder though; we'll have to watch for breakage once the limit is again reduced. – Mike.lifeguard  | talk 15:09, 11 December 2007 (UTC)

title: Template talk:Archive list long


text:
Web 2.0 and Emerging Learning Technologies/Methods of Personalized Learning Environments (PLE)

Even though PLE differ from case by case and almost the process has no end， are there some practical methods or tips for the novice begin to establish of his PLE? Here some methods and suggestions.

1. Necessary tools

There are many social tools for establishing PLE， how we make a selection？ Here some tools are necessary.

(1) Social bookmark

Why we need to use the social bookmark such as del.icio.us?

With the development of WEB2.0, the website numbers are going up exponentially, which brings the problem for an individual how to manage the URL resources effectively and efficiently.

Social bookmark provides a new way to make use of URL resources. Unlike the tradition way we just store some useful URLs to the favorite folder by web browser to our own computer， through using social bookmark, we can find more related useful URL resources and we have more opportunities to make connection with other people we are interested in.

As an example, here is the course announcement "The Web 2.0 and Participatory e-Learning" released by professor Curt Bonk, if you collect this URL by social bookmark del.icio.us, then you can find there are so many people share the same interests with you, and further you can add some people to your network in del.icio.us. In this way, you can establish your own PLE step by step.

(2)RSS Reader

Why we need to use the RSS reader such as Blogline or Google reader?

The content of WEB2.0 is mainly generated by users, which also brings the problem for an individual how to get update content in time. If we still behave in the traditional way that is visiting different websites one by one through web browser, we couldn't afford the time cost. In additional, you are not sure which website has been updated.

RSS reader can help to solve this problem. You just need to add the rss feed of the website which you are interested in to your RSS reader. You get update information from different websites just by checking your RSS reader. In this way, you not only can save much time, but also you have the ability to read more information from more different websites.

RSS reader is a necessary tool for an individual to establish his PLE.

(3)Tagging

From a technical perspective, it is tag which makes WEB2.0 different from WEB1.0. There need a new way to organize the content which generated by different users. The new way is tag. In taxonomy term, it is called folksonomy.

By tagging his content, an individual not only adapts a new way to organize his own content, but also adapts a new way to make connection with other people.

During the search using tag, not only you can find many related contents which you want to find, but also you can find some persons who share the same interests with you.

So, tagging is an important behave during the process of establish one's own PLE.

(4)Blog

(5)WIKI

2. Cop Community of Practise

3.PKM Personal knowledge management


text:
IB Biology Practical Investigations/Human Health and Physiology/Mock HIV test and Virtual ELISA test

Mock HIV Test and Virtual ELISA for Lupus
TEACHING OBJECTIVE:
 * to illustrate the use of antibodies in the diagnostic ELISA test for HIV and Lupus.

TASK OUTCOMES: a. Follow a simplified ELISA test to determine which 'patients' are HIV positive.
 * By the end of this activity, students will be able to:

b. Follow a detailed virtual lab protocol for the ELISA test for lupus.

c. Outline the use of antibodies in diagnostic medicine.

TIME REQUIRED:
 * 60-90 minutes

INTRODUCTION:  The ELISA test detects antibodies to a pathogen in blood serum and shows a positive result with a colour change. Dilutions of blood serum allow levels of antibodies (and thus the development of the disease) to be estimated. In this activity, students will carry out a simple test on mock serum samples and will go through all the steps of the ELISA in the virtual lab activity from the Howard Hughes Medical Institution.

ESSENTIAL LINKS
 * Description and worksheet for the HHMI virtual lab.
 * Direct Link to HHMI Immunology Lab Activity

MATERIALS AND EQUIPMENT:
 * Virtual lab: worksheet and internet link to site above (requires Flash)
 * Mock HIV Test (for each pair/ group):
 * Lead nitrate and potassium iodide solutions
 * Dimple tray (min 11 wells)
 * 11 x 100ml volumetric flasks, marked A-1:2 A-1:10 A-1:100; B-1:2 B-1:10 B-1:100; C-1:2 C-1:10 C-1:100; Positive Control; Negative Control; HRP
 * A set of clean dropping pipettes

INSTRUCTIONS:  Prac Set Up:
 * Carry out the mock HIV test first, using it as a chance to explain the method of the ELISA.
 * Follow this up with the virtual lab and the worksheet for students to add depth to their knowledge.
 * As outlined in the image 'setup'.
 * Each group also needs a flask containing 20ml Lead nitrate. Label this 'HRP' (for anti-human antibody).

Instructions
 * Explain that serum samples have been collected and diluted and are presented in the flasks. the ELISA plate (dimple tray) has been coated with HIV antigen.
 * Add a few drops of 'serum' to the appropriate wells. Take care not to contaminate them.
 * Explain at this point that they would normally be washed in buffer, to remove all traces of unattached antibodies.
 * To each of the wells, add a few drops of 'HRP. If antibodies are present, a reaction occurs causing a colour change.
 * Students record and analyse their results:

Who is positive/ negative/ needs more testing?

SAFETY/ RISK ASSESSMENT
 * eye protection for KI and PbNO3
 * wash all equipment thoroughly and do not ingest.
 * we aren't using real HIV, so don't worry.

 IMAGES AND PRAC SETUP


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Horticulture/Lamium purpureum

Red Deadnettle (Lamium purpureum) is a herbaceous plant native to Europe and Asia. Though superficially similar to a nettle in appearance, it is not related and does not sting, hence the name "deadnettle". Outside of its native range, it is a common weed of cultivated areas; it is listed as an invasive species in some parts of North America.

Description
It grows to 5–20 cm (rarely 30 cm) in height. The leaves are green at the bottom and shade to purplish at the top; they are 2–4 cm long and broad, with a 1–2 cm petiole (leaf stalk), and wavy to serrated margins. It is often found alongside Henbit Deadnettle (../Lamium amplexicaule/), which is easily mistaken for it since they both have similar looking leaves and similar bright purple flowers; they can be distinguished by the stalked leaves of Red Deadnettle on the flower stem, compared to the unstalked leaves of Henbit Deadnettle.

The flowers are bright red-purple, and may be produced throughout the year, including mild weather in winter. This allows bees to gather its nectar for food when few other nectar sources are available. It is also a prominent source of pollen for bees in March/April (in UK), when bees need the pollen as protein to build up their nest.

Uses
Young plants have edible tops and leaves, good in salads or in stirfry as a spring vegetable. If finely chopped it can also be used in sauces.

title: Horticulture/Lamium purpureum


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Horticulture/Acer saccharum

Ecology
The Sugar Maple is an immensely important species to the ecology of many forests in North America. Pure stands are common, and it is a major component of many forest types. It often forms associations with the American Beech, forming the beech-maple forest type, common in northern areas. Other associations include Sugar Maple-Yellow Birch (which is most important beyond the northern limit of beech), Sugar Maple-American Basswood, Sugar Maple-White Ash and Sugar Maple-Ironwood-Red Oak. Sugar Maples engage in hydraulic lift, drawing water from lower soil layers and exuding that water into upper, drier soil layers. This not only benefits the tree itself but also many other plants growing around it. Sugar Maple is among the most shade tolerant of large deciduous trees. Among North American maples its shade tolerance is exceeded only by the Striped Maple, a smaller tree. Like other maples, its shade tolerance is manifested in its ability to germinate and persist under a closed canopy as an understory plant, and respond with rapid growth to the increased light formed by a gap in the canopy. The sugar maple can grow comfortably in any type of soil, except sand.

Human influences have contributed to the decline of the Sugar Maple in many regions. Its role as a species of mature forests has led it to be replaced by more opportunistic species in areas where forests are cut over. The Sugar maple also exhibits a greater susceptibility to pollution than other species of maple. Acid rain and soil acidification are some of the primary contributing factors to maple decline. Also, the increased use of salt over the last several decades on streets and roads has decimated the sugar maple's role as a "street-front" tree.

In some parts of eastern North America, particularly near urbanized areas, the Sugar Maple is being displaced by the Norway Maple. The Norway Maple is also highly shade tolerant, but is considerably more tolerant of urban conditions resulting in the Sugar Maple's replacement in those areas heavily disturbed by human activities.

Conservation
The sugar maple is widespread, and is considered secure, except at the edges of its range.

Cultivation and uses
The Sugar Maple is one of the most important Canadian trees, being (with Black Maple) the major source of sap for making maple syrup; Sugar Maple being regarded as slightly better. Many maples can be used as a sap source for maple syrup, but none of the others are as good as these two.

The wood is one of the hardest of the maples, and is prized for furniture and flooring. Bowling alleys and bowling pins are both commonly manufactured from sugar maple. Trees with wavy wood grain, which can occur in curly, quilted and "birdseye maple" form, are especially valued. Maple is also the wood used for basketball courts, including the floors used by the NBA, and it is a popular wood for baseball bats, along with white ash.

The Sugar Maple is a favorite street and garden tree, because it is easy to propagate and transplant, is fairly fast-growing, and has beautiful fall color; however, its intolerance of pollution and compacted soils common to inner city conditions make it a frequent victim of maple decline. It also has some of the most dense shade to be found in shade trees. The shade and the shallow, fibrous roots may interfere with grass growing under the trees. Deep well-drained loam is the best rooting medium, although Sugar Maple can grow well on sandy soil which does not become excessively dry. Light (or loose) clay soils are also well known to support Sugar Maple. Poorly drained areas are unsuitable and the species is especially short-lived on flood-prone clay flats. Its salt tolerance is low and it is very sensitive to boron.
 * Cultivars
 * 'Apollo' - columnar.
 * 'Arrowhead' - pyramidal crown.
 * 'Astis' (Steeple®) - heat-tolerant; good in southeastern USA. Oval crown.
 * 'Bonfire' - fast-growing.
 * 'Columnare'
 * 'Fall Fiesta' - tough-leaved, colorful in season, hardy.
 * 'Green Mountain' - durable foliage resists heat and drought.
 * 'Legacy' - tough, vigorous and popular.
 * 'Monumentale' - columnar.
 * 'Newton Sentry' - very narrow.
 * 'Sweet Shadow' - lacy foliage.
 * 'Temple's Upright' - columnar.
 * 'Unity' - very hardy Manitoba cultivar.

Sugar Maple is the State Tree of New York, Vermont, West Virginia and Wisconsin.

title: Horticulture/Acer saccharum


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Horticulture/Salix discolor

Salix discolor (American Pussy Willow ) is a species of willow native to North America, one of two species commonly called Pussy Willow.

It is native to the northern forests and wetlands of Canada (British Columbia east to Newfoundland) and the northeastern contiguous United States (Idaho south to Wyoming, and east to Maine and Maryland).

Description
It is a weak-wooded deciduous shrub or small tree growing to 6 m tall, with brown shoots. The leaves are oval, 3-14 cm long and 1-3.5 cm broad, green above and downy grey-white beneath. The flowers are soft silky silvery catkins, borne in early spring before the new leaves appear, with the male and female catkins on different plants (dioecious); the male catkins mature yellow at pollen release. The fruit is a small capsule 7-12 mm long containing numerous minute seeds embedded in cottony down.

Uses
As with the closely related ../Salix caprea/ (European Pussy Willow), it is also often grown for cut flowers.

Like other willows, it contains salicin, and was used by Native Americans as a painkiller.

title: Horticulture/Salix discolor


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Horticulture/Symplocarpus foetidus

Eastern Skunk Cabbage, Clumpfoot Cabbage, Foetid Pothos, Meadow Cabbage, Polecat Weed, Skunk Cabbage, or Swamp Cabbage (Symplocarpus foetidus), commonly known as simply Skunk Cabbage, is a low growing, foul smelling plant that prefers wetlands. It can be found naturally in eastern North America, from Nova Scotia and southern Quebec west to Minnesota, and south to North Carolina and Tennessee, and also in northeastern Asia, in eastern Siberia, northeastern China and Japan. It is the only species in the genus, although the genus Lysichiton is similar. Skunk cabbage is protected as a state endangered plant in Tennessee.

Description
The leaves are large, 40-55 cm long and 30-40 cm broad. It flowers early in the year; the flowers are produced in a 5-10 cm long spadix contained within a spathe, 10-15 cm tall and mottled purple in colour. It flowers in the early spring, when only the flowers are visible above the mud, with the stems buried below and the leaves emerging later. The rhizome is often 30 cm thick.

Its name is derived from its odor, which is rather mild as long as the plant remains intact. To fully appreciate why the plant is so named, one need only tear off a fresh leaf, releasing a pungent odor. While not considered edible, the plant is not poisonous to the touch. Though unpleasant, the smell is not harmful. The foul odor attracts its pollinators, scavenging flies, stoneflies, and bees. The odor in the leaves may also serve to discourage large animals from disturbing or damaging this plant which grows in soft wetland soils.

Skunk cabbage is notable for its ability to produce heat of up to 15-35° C above air temperature by cyanide resistant cellular respiration in order to melt its way through frozen ground, placing it among a small group of plants exhibiting thermogenesis. Although flowering whilst there is still snow and ice on the ground it is successfully pollinated by early insects that also emerge at this time. Some studies suggest that beyond allowing the plant to grow in icy soil, the heat it produces may help to spread its odor in the air. Carrion-feeding insects that are attracted by the scent may be doubly encouraged to enter the spathe because it is warmer than the surrounding air, fueling pollination.

Eastern Skunk Cabbage has contractile roots which contract after growing into the earth. This pulls the stem of the plant deeper into the mud, so that the plant in effect grows downward, not upward. Each year, the plant grows deeper into the earth, so that older plants are practically impossible to dig up. It is thought possible that it may be able to live for hundreds of years. They reproduce by hard, pea-sized seeds which fall in the mud and are carried away by animals or by floods.

Growing Conditions
Does best in true wetlands, but can survive in moist soils. Full sun to fairly dense shade.

Uses
In the 19th century the U. S. Pharmacopoeia listed eastern skunk cabbage as the drug "dracontium". It was used in the treatment of respiratory diseases, nervous disorders, rheumatism, and dropsy. In North America and Europe, skunk cabbage is occasionally cultivated in water gardens. Skunk cabbage was used extensively as a medicinal plant, seasoning, and magical talisman by various tribes of Native Americans.

Propagation
Easily propagated by division, though the plant is quite aromatic in the underground parts.

Pests and Diseases
Leaf blights are frequent but not fatal.

title: Horticulture/Symplocarpus foetidus


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Horticulture/Acer japonicum

Acer japonicum (Downy Japanese Maple or Fullmoon Maple; Japanese: ハウチワカエデ hauchiwakaede) is a species of maple native to Japan, on Honshū, Hokkaidō, Kyūshū (Nagasaki Prefecture), and also southern Korea.

It is a small deciduous tree growing to 5–10 m (rarely 15 m) tall, with a trunk up to 40 cm diameter. The bark is smooth on young trees, becoming rough and scaly on old trees. The shoots are slender, and thinly downy with whitish hairs. The leaves are rounded, 7–15 cm diameter with 9–13 (rarely 7) serrate lobes incised to half or less of the diameter of the leaf; they are downy at first with white hairs, the hairs mostly lost by late summer except on the veins and the underside of the leaf; the petiole is 2–4 cm long and hairy. In autumn, the leaves turn bright orange to dark red. The flowers are 1 cm diameter, dark purplish-red with five sepals and petals; they are produced 10–15 together in drooping corymbs in early spring as the leaves start to open. The fruit is a paired samara with the nutlets 7 mm diameter with a 20–25 mm wing, hanging under the leaves.

The closely related species ../Acer shirasawanum/ (Japanese, オオイタヤメイゲツ ooitayameigetsu) from southern Japan is sometimes included as a subspecies of A. japonicum. It is distinct in its hairless shoots, and usually smaller leaves. Another related species, ../Acer sieboldianum/ (Japanese: コハウチワカエデ kohauchiwakaede), is best distinguished by its yellow (not red) flowers, and smooth bark even on old trees. It is more easily distinguished from ../Acer palmatum/, as that species rarely has leaves with more than seven lobes.

Cultivation
A. japonicum is frequently cultivated as an ornamental plant in temperate regions of Europe, North America, and elsewhere, though much less commonly than A. palmatum. In cultivation, it is often only a shrubby tree with multiple trunks joining at ground-level.

Its preferred growing conditions are similar to those of A. palmatum, but it is sometimes considered more tolerant of cold, especially compared to the more delicate cultivars of the latter.

Numerous cultivars have been selected, some of which have their own common names (e.g. "Grape-leaf maple" for A. japonicum 'Vitifolium'). Other popular cultivars are 'Aconitifolium' which has deeply incised leaves, and 'Green Cascade', with drooping to pendulous branches. Because of their variation from the wild species, some cultivars are difficult to assign to species, and they have often been mis-labeled as cultivars of the other related species; notably 'Aureum' has commonly been cited as a cultivar of A. japonicum, but is actually derived from A. shirasawanum.

Cultivars of this maple are found in almost every maple collection including ../Esveld Aceretum/ (Boskoop, Netherlands) and the large Acer section of ../Arnold Arboretum/ (Boston, Massachusetts). They are also common in more general collections of horticulture.

title: Horticulture/Acer japonicum


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Blender 3D: Noob to Pro/Landscape Modeling III: Exporting as a Heightmap

In this tutorial, I will show you how to export your beautiful terrain to a heightmap that can be used in most 3D graphics engines. The benefit to doing this as opposed to just exporting your mesh is that many engines have a special process for dealing with terrains as opposed to regular meshes where it divides the terrain up into different sections so that it can subdivide regions closer to the camera more for greater detail, and also cull (not render) regions outside the camera's field of view, saving precious processing time. This structure is called an oct tree and is a highly optimized way to render large meshes such as terrains.

Before I begin, I must give credit to the Creating a Heightmap from a Plane tutorial on the Blender wiki. This is how I learned to do this trick, and most of what I will cover came from this tutorial. I'm simply including it here with the other landscaping tutorials I've written for convenience.

A Word About Heightmaps
I will briefly cover what a heightmap is and how it's useful for those who may not know. If you are familiar with heightmaps, you can skip ahead to the next section.

A heightmap is a grayscale image that uses various shades of gray to represent different elevations across a map. Since the images are 8-bit (with the exception of some RAW formats that are 16-bit), you have 256 different shades of gray, ranging from pure black (0) to pure white (255). Black represents the lowest elevation on the map, while white represents the highest. Many 3D graphics engines already have functions to read in a heightmap and generate terrain from it. The way it does this is it creates a grid of vertices (like we are going to do in Blender in just a moment), and uses the heightmap to determine the elevation of each point on the grid. The more intense the pixel color (the closer it is to white), the higher the elevation of that vertex. In most cases, if the resolution of the heightmap is smaller than the resolution of the terrain, the engine will interpolate the vertices in between those set by the heightmap. For example, if your heightmap is 256x256 and your terrain is 1024x1024, your heightmap will determine the elevation of every fourth vertex, and the three in between will be interpolated.

Note that these values do not represent the absolute height of any given pixel, but rather the height relative to the rest of the map. That is, your heightmap does not represent a landscape with altitudes ranging from 0 to 256. When importing a heightmap, you can specify the minimum and maximum altitudes for the map, and the whole thing gets scaled. For example, suppose you decide the minimum is 1000 feet, and the maximum is 5000 feet. When the terrain is rendered, black pixels will represent 1000, white pixels will represent 5000, and a pixel that is exactly in between black and white (128) will represent 3000 feet (half of the sum of min and max). This makes heightmaps relatively flexible.

Unfortunately, as you may have already noticed, there is a limitation of using heightmaps. Since you only have 256 shades of gray, you only have 256 possible elevations. This causes a problem. No matter how precise your vertices may be in the mesh that you model, no matter how smooth you may have it looking, each point will get rounded off to an integer value between 0 and 255. When used to render a terrain, this can cause a "stair step" effect as the terrain goes from one discrete elevation to the next instead of making a smooth transition. But there are ways to avoid this, which I will cover later.

I apologize if you're scratching your head right now saying "Huh?" For a further explanation and example, check the Wikipedia page on heightmaps.

Creating the Material
To begin this tutorial, I will assume that you already have a landscape that you want to create a heightmap for. If not, read my first tutorial, Landscape Modeling I: Basic Terrain, to quickly create something. WORD OF CAUTION!!! If you've already created a landscape, try to remember the exact size of the plane that you used. If you're about to make one, it's okay to scale the plane to have a larger surface to work with, but REMEMBER how much you scale it by. This will make things easier later. I recommend just working with the default 2x2 plane or grid and zooming in on it. You may also want to backup your scene since we'll be changing a few things

To create the material we need, do the following steps: Note: to remove a material, I think you need to go to the links and pipeline window in the shader section and click the little "X" underneath the words "link to Object"
 * Remove any existing materials that may be applied to the terrain.
 * Add a new material in the Shading tab (F5).
 * Go to the Textures tab (F6) and add a new texture. This should be the only texture on your material.
 * From the Texture Type drop down menu, select Blend.
 * In the same window, find the Colors tab and select Colorband. This will let us define the blend pattern, which by default fades from black with full transparency to a solid cyan.  Why cyan?  I have no idea.  It's an odd default.
 * Select the black color by clicking on the left side of the colorband. You should see a little black and white bar selected.
 * Increase the Alpha all the way up to 1 by adjusting the slider labeled "A".
 * Select the cyan color and change this to a solid white.
 * What you have now should look like my colorband below.
 * Return to the Materials tab (the red ball icon next to the cheese looking icon).
 * In the Material pane, select the Shadeless option to disable lighting on the material.
 * To the right, find the pane labeled Map Input. In the bottom of this pane is a grid that by default reads:

XYZ XYZ XYZ

 * Set all three rows to Z so that the texture will map entirely to the Z coordinate.
 * In the preview window to the left, if you select the sphere or cube you should see that it goes from black on the bottom to white on the top. That's the effect we want for the terrain.  Remember, in a heightmap, black represents the lowest point and white the highest.
 * Finally, switch back to the Editing tab (F9) and click the Set Smooth button to enable Gouraud shading so that everything appears smooth.

Setting up the Camera
That's all we need to do for the terrain itself. Now what we're going to do is setup the camera in such a way that when we render the scene we'll get an orthographic projection straight down on the terrain so that we can save it as our heightmap.

 * If you still have any lights or cameras in the scene, delete them.
 * Switch to the top view (NUM7) and place the 3D cursor at the origin (0, 0, 0) by left clicking near the origin, hitting SHIFT+SKEY and selecting Cursor to Grid. (An easier way is: hitting 'SHIFT+SKEY' and selecting 'Cursor to Center')
 * Add a new camera, Space->Add->Camera. This will add a new camera to the scene that is looking straight down.
 * Switch to a side view (NUM1 or NUM3) and move the camera up the Z axis so that it is above the highest point in your terrain. Even though the view is going to be orthographic, and therefore distance doesn't matter, the entire terrain still needs to be in front of the camera.
 * Now, with the camera selected, go to the Editing tab (F9) and select the "Orthographic" button. This will change the camera to an orthographic projection which basically ignores the z-coordinate for all vertices (except for determining which pixels should be in front of others).
 * Just above the orthographic button is a value labeled "Scale". Remember earlier when I told you to remember how big your terrain is?  This is why.
 * Change the Scale of the lens (default: 6) to match the size of your terrain. If you left the plane the default size, this should be 2.  If you scaled the plane up by a factor of 20, as suggested in the "Landscape Modeling I: Basic Terrain" tutorial, this should be 40 (the plane is initially 2 units square).
 * Now go to the scene tab (F10) and under Format, change the SizeX and SizeY to be the size you want your heightmap to be. For most graphics engines, this is required to be either a power of 2 (2^n) or one more than a power of 2 (2^n+1).  So try something like 256 (or 257 if you need it to be 2^n+1).
 * Now, if you switch to the camera view (NUM0) you should see a "flat" square that completely fills the dotted box which represents the camera's field of view.
 * Render the scene (F12). You should be looking at your heightmap.  Hit F3 to save the rendered image and you're good to go!

Since this image has no color, and some engines require that your heighmap be a grayscale image (only one color channel instead of three), select the BW button in the Format pane before rendering. This will render it as a grayscale image instead of a color image.

Avoid Stair-Stepping
As mentioned earlier, exporting the heightmap as an 8-bit image (Blender doesn't support any 16-bit formats that I'm aware of) has the drawback that you only have 256 discrete height values which can cause a stair-step effect when the terrain is subdivided. Ideally, you could use an application that can export the image in a 16-bit raw format, such as Terragen. But this is a Blender tutorial, so we'll not go into that. =P

Reducing the resolution
One way you can "smooth" out the rendered terrain is to actually reduce the resolution of the heightmap. This may sound counter intuitive, but bear with me. Suppose you have a heightmap that is a simple blend from black to white going from left to right. If your heightmap is 1024x1024, you will get 4 columns of each height since you only have 256 different values. In other words, your grayscale will look something like this:

00001111222233334444...

00001111222233334444...

00001111222233334444...

00001111222233334444...

00001111222233334444...

00001111222233334444...

If you try to render terrain from this, you'll get 4 points with 0 altitude, 4 with 1, 4 with 2, and so on, creating the stair-step effect.

Now suppose you make the same heightmap, but reduce its size to 256x256. Now you'll have 1 column for each height, and your grayscale will look something like this:

012345678...

012345678...

012345678...

012345678...

You may be thinking, "But then my terrain will be smaller, or less detailed." But it turns out the opposite is actually true. Consider applying the above heightmap to a terrain that is 1024x1024. The values from your heightmap will be applied to every 4th vertex, and the ones in between will be interpolated. So instead of having something like:

0.0  0.0   0.0   0.0   1.0   1.0   1.0   1.0   2.0

which is what you would get with the 1024x1024 heightmap, you'll actually get something like this:

0.0  0.25   0.5   0.75   1.0   1.25   1.5   1.75   2.0

Where the integers are the values from your heightmap and the fractions are interpolated values. This is assuming that whatever engine you are using will interpolate the values between heights read in from the heightmap.

At the present time, this is the only method I have verified that helps reduce the effects of stair-stepping. As I try different techniques I will update this page with them. For example, I know that Adobe Photoshop can export images in 16-bit raw formats, but I haven't tried it yet so I don't want to suggest it as a solution.


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Horticulture/Acer platanoides

Acer platanoides (Norway Maple) is a species of maple native to eastern and central Europe and southwest Asia, from France east to Russia, north to southern Scandinavia and southeast to northern Iran. It is widely cultivated elsewhere, and is also an invasive in some areas.

Description
It is a deciduous tree growing to 20–30 m tall with a trunk up to 1.5 m diameter, and a broad, rounded crown. The bark is grey-brown and shallowly grooved; unlike many other maples, mature trees do not tend to develop a shaggy bark. The shoots are green at first, soon becoming pale brown; the winter buds are shiny red-brown. The leaves are opposite, palmately lobed with five lobes, 7–14 cm long and 8–20 cm (rarely 25 cm) across; the lobes each bear one to three side teeth, and an otherwise smooth margin. The leaf petiole is 8–20 cm long, and secretes a milky juice when broken. The autumn colour is usually yellow, occasionally orange-red. The flowers are in corymbs of 15–30 together, yellow to yellow-green with five sepals and five petals 3–4 mm long; flowering occurs in early spring before the new leaves emerge. The fruit is a double samara with two winged seeds, the seeds are disc-shaped, strongly flattened, 10–15 mm across and 3 mm thick. The wings are 3–5 cm long, widely spread, approaching a 180° angle. It typically produces a large quantity of viable seeds. It is not particularly long-lived, with a maximum age of around 250 years.

Norway Maple is a member (and is the type species) of the section Platanoidea Pax, characterised by flattened, disc-shaped seeds and the shoots and leaves containing milky sap. Other related species in this section incluse ../Acer campestre/ (Field Maple), ../Acer cappadocicum/ (Cappadocian Maple), ../Acer lobelii/ (Lobel's Maple), and ../Acer truncatum/ (Shandong Maple). From Field Maple, Norway Maple is distinguished by its larger leaves with pointed, not blunt, lobes, and from the other species by the presence of one or more teeth on all of the lobes.

It is also frequently confused with the more distantly related ../Acer saccharum/ (Sugar Maple). Sugar Maple is easy to distinguish from this species by the clear sap in the petiole (Norway Maple has white sap in the petiole). The tips of the points on Norway Maple leaves reduce to a fine "hair", while the tips of the points on Sugar Maple leaves are on close inspection rounded. On mature trees, Sugar Maple bark is more shaggy, while Norway Maple bark has small, often criss-crossing grooves. While the shape and angle of leaf lobes vary somewhat within all Maple species, the leaf lobes of Norway Maple tend to have a more triangular shape, in contrast to the more squarish lobes often seen on Sugar Maples. The seeds of Sugar Maple are globose, while Norway Maple seeds are flattened. Sugar Maple usually has a brighter orange autumn colour.

Varieties
Many cultivars have been selected, with distinctive leaf shape or coloration such as the dark purple of 'Crimson King' and 'Schwedleri', the variegated leaves of 'Drummondii' and 'Emerald Queen', and the deeply divided, feathery leaves of 'Dissectum' and 'Lorbergii'. The purple-foliage cultivars have orange to red autumn colour. 'Columnare' is selected for its narrow upright growth.

Uses
The wood is hard, yellowish-white to pale reddish, with the heartwood not distinct; it is used for furniture and turnery.

It has been widely introduced into cultivation in other areas, including western Europe northwest of its native range. It grows north of the Arctic Circle at Tromsø, Norway. In North America, it is grown as a street and shade tree. It is favoured due to its tolerance of poor, compacted soils and urban pollution. As a result of these characteristics, Norway Maple is displacing locally native hardwoods in some parts of North America and is considered invasive in some states, but is still widely used for urban plantings in many areas. Norway Maple itself is threatened in a few areas by the ../Asian long-horned beetle/, which eats through the trunk of trees, often killing them.

Maintenance
Bad crotching can be an issue, and since the wood is relatively weak the tree can easily split in windstorms.

Propagation
Cultivars are propagated by cutting or grafting, otherwise the tree produces abundant fertile seed.

Pests and Diseases
Norway Maple is generally free of serious diseases, though can be attacked by the powdery mildew ../Uncinula bicornis//, and verticillium wilt disease caused by ../Verticillium/ spp.

title: Horticulture/Acer platanoides


text: User talk:204.11.190.31

title: User talk:204.11.190.31


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C++ Programming/Programming Languages/Paradigms/Encapsulation

Encapsulation
Encapsulation (also known as information hiding) is a concept commonly used on large software projects to allow for extensibility. The principal behind encapsulation is to hide the inner workings of a class from the code that uses the class, only exposing the essentials.

Why Bother?
Team development projects often split up tasks. Designing clean, easy to understand interfaces makes code easier to understand. If a data member of a class written by Team A is used by Team B, and the class changes a way the data member works, it can break compatibility with Team B's code. Not only is maintaining data members of a class very difficult, it can also be quite confusing to clients. The interface of an encapsulated class is like a contract to clients, stating what it is capable of doing. The client shouldn't care how it is done, in fact it can be upgraded in the future, as long as it complies with the same interface.

Implementation
To completely encapsulate a class, all data members of the class must be private. In designing the class, it must be determined what data must be accessible, and what can be kept completely hidden. The data to be made public will require "accessor functions," which can allow data to be read or stored in private data members.