OpenLLM-France/wikimedia huggingface dataset:
# Introduction to Programming Languages/Array Cost Model

We say that a data-structure is random access if the cost to read (or update) any element that it stores is the same, regardless of its position. Functional lists are clearly not random access: reading the n-th element is O(n). Arrays in C or Java, on the other hand, are. There are other data-structures which are also random access, at least on the average, such as hash-tables. Henceforth, we shall focus on C-style arrays. The key to random access lay on the fact that an array is stored contiguously in memory. Thus, an access such as a[i], in an array of type T, can be translated to the expression *(a + i). The same principle works for multidimensional arrays as well. As another example, a[i][j] in a 2-dimensional array of M lines and N columns, in C, translates to: *(a + i*N + j). However, even when we restrict ourselves to arrays, it is still difficult to ensure the same access cost always. The culprit is something called locality. To explain what is locality, let's consider two loops:
This program runs at different speeds, depending on which loops executes (on an Intel core i5 at 1.4GHz):
So, what is going on with this example? The same number of operations is performed, regardless of which loop runs. However, the first loop is 3.5x faster. As mentioned before, the key feature playing a role in these results is locality. Modern general purpose computer architectures use a cache. The cache is divided in lines. Data is not brought from main memory into the cache in individual pieces. Instead, a whole line is brought at once. If a program can access multiple datum on the same line, then memory trips can be avoided. On the other hand, if data is accessed across different lines, then multiple trips to the main memory must be performed. These trips are expensive, and they account for most of the running cost of this example.
How should a program be implemented, so that it can benefit more from locality? The answer is: it depends on the programming language. C organizes data in a row-major scheme. This means that in a 2-dimensional array, data on the same line are placed next to each other in memory. However, data in the same column can be quite far away. Cells in the same column, but in adjacent lines, will be N elements apart, where N is the line size in the 2-dimensional array. On the other hand, there are programming languages that organize data in column-major order. An example is Fortran. In this case, it is more efficient to fix columns and vary lines, while traversing 2-dimensional arrays.
← Unification Cost Model · Simple Predicates →
# Introduction to Programming Languages/Closures
### Closures

A closure is an implementation of a function, plus a table that binds values to the free variables that appear in the body of the function. A variable v is free in a function body f if v is used inside f, but it is not declared in f. Closures give the developer a way to pass functions around, together with some information about the context where these functions were created. Pragmatically speaking, closures allow the developer to write factories of functions. For instance, below we have a Python function that produces unary sums:
In the above example we notice that variable a is free in the body of function unarySum. This variable has been declared in the scope of the function unarySumFactory, and the fact that it can be referenced inside unarySum poses to language designers an implementation problem. Normally once a function returns its value, the space reserved for its activation record is deallocated. However, if this space is deallocated, variable a in our example would no longer have a storage location once unarySumFactory had returned a value. To circumvent this difficulty, closures are implemented as pairs (f, t), where f is a pointer to the implementation of the function, and t is a pointer to a table with all the free variables used in f associated with values.
Because the closure might outlive the function that has created it, normally the pair (f, t), and the contents of table t are allocated in the heap. The code below, written in C, implements the call unarySumFactory seen before. C does not have syntactic support for closures. Nevertheless, we can implement closures by combining high-order function calls with dynamic heap allocation.
← Definition and Examples · Partial Application →
# Introduction to Programming/Components of a computer
## Central Processing Unit

At the heart of a computer is the Central Processing Unit (CPU) which performs the logical and arithmetical operations on streams of numbers as controlled by a “program” which is itself a stream of numbers. The CPU has access to the computer memory which the computer uses to hold numbers. The CPU can also send and receive numbers from input and output devices.

## Random Access Memory

The Random Access Memory (RAM) is the memory where the computer holds information that is currently using. The memory behaves a bit like a series of numbered boxes, each of which can hold a number which can be stored or later retrieved by the CPU. Note that when the computer power supply is switched off, the contents of the RAM becomes lost.

## Read Only Memory

Computers contain a Read Only Memory (ROM) chip that retains its information when the computer power supply is switched off. The Read Only Memory chip contains the BIOS program that enables the computer to startup and load other programs.

## Devices and Peripherals

Devices are things that are part of the computer or attached to it, and are used for input or output, storage or communications, such as the disk drives, network cards, video cards, etc.
Peripherals are devices that are externally connected to the computer, such as the keyboard, display, printer, mouse or joystick.
# General Topology

* Definition, characterisations
* Constructions
* Bases
* Continuity continuity and constructions
* Separation separation and constructions
* Countability, density
* Compact spaces proper and continuous maps are closed, alexandroff and stone-cech compactifications, tychonoff, compactness and constructions, paracompactness and partition of unity
* Filters
* Connected spaces connectedness and constructions
* Miscellaneous spaces
* Nets
* Order topology and semicontinuity
* Uniform spaces uniform (equi-)continuity, uniform completion, image of complete spaces in complete spaces, closed subspace of complete space is complete, Tietze–Urysohn for normal spaces and equicontinuity
* Metric spaces pseudometrics (alexandroff in metric setting? or uniform?), metrizability theorem
* The compact-open topology
* Homotopy things which are invariant under homotopy
* Covering spaces proper local homeomorphisms are precisely finite covering maps
* Fiber bundles and fibrations
* CW complexes
* Simplicial complexes
* Pointed spaces and support

## Sources

* Bourbaki, General Topology
* Grothendieck TVS
* Hatcher Algebraic Topology
* Lamotke Semisimpliziale algebraische Topologie
# General Securities Representative Exam/Debt Securities
## Debt Securities

Another method a corporation can raise capital is through Debt Securities which are also called bonds. Bonds are loans to the corporation made by the investor to be repaid at a stated future date at a set interest rate. Although, bonds are not limited to corporations. The U.S. government can issue government bonds. Also municipalities such as states, cities, and such can issue municipal bonds. Bonds can also be called funded debt, and are considered long term debt because they are usually issued for at least 5 years or more. Bonds are rated by Moody's, S & P and Fitch.
Each bond has a document or certificate that describes the terms and conditions of the loan. This document is called an indenture.
Some items to consider when investing in a bond are:
* Reinvestment risk
* Callable risk
* Interest rate risk
* Default risk
Convertible bonds are bonds that corporations issue that give the investor the right to convert the bonds to common stock.
A corporation can also issue commercial paper, which is generally traded overnight and used to shore up financing and cash, and has a maturity of less than 1 year.
# General Topology/Countability, density

Definition (dense):
Let $X$ be a topological space and let $A\subseteq X$ be a subset. $A$ is called dense if and only if ${\overline {A}}=X$.
Definition (first-countable):
Let $X$ be a topological space. $X$ is called first-countable iff for all $x\in X$ the neighbourhood filter $N(x)$ has a countable basis.
Definition (second-countable):
Let $X$ be a topological space. $X$ is called second-countable iff the topology of $X$ has a countable basis.
Since subsets of countable sets are countable and the open neighbourhoods generate $N(x)$, second-countability implies first-countability.
Definition:
separable space
Proposition:
second-countable spaces are separable
Proof: Let $(U_{n})_{n\in \mathbb {N} }$ be a basis of the topology of $X$ and choose $x_{n}\in U_{n}$. Then $S:=\{x_{n}|n\in \mathbb {N} \}$ is countable and dense. $\Box$
Proposition:
subspace of second-countable space is second-countable
Proof: Any countable basis $(U_{n})_{n\in \mathbb {N} }$ of the topology of $X$ induces a countable basis $(S\cap U_{n})_{n\in \mathbb {N} }$ of the subspace topology on $S$. $\Box$
Proposition:
continuous function into Hausdorff space is uniquely determined by dense subspace
Proof: Let $x\in X$ be arbitrary, and let $V\subseteq Y$ be any neighbourhood of $G(x)$. By continuity of $G$ we may find a neighbourhood $U$ of $x$ that is mapped completely into $V$. Analogously, whenever $V'$ is a neighbourhood of $F(x)$, we find a neighbourhood $U'$ mapping completely into $V'$. Then $U\cap U'$ is mapped completely into $V\cap V'$, so that $F(x),G(x)\subseteq V\cap V'$ for any open neighbourhoods $V$ of $G(x)$ and $V'$ of $F(x)$. If $F(x)\neq G(x)$, then $V\cap V'=\emptyset$ for suitable $V,V'$ as above by the Hausdorff condition, a contradiction to $G(x)\in V\cap V'$. Hence, $F(x)=G(x)$. Since $x$ was arbitrary, we conclude. $\Box$
# Macedonian/Alphabet

<< Macedonian | Macedonian Alphabet | Macedonian Grammar | Macedonian Numbers | Macedonian Verbs | Macedonian Words | Common phrases >>

## The Macedonian Alphabet

| Letter | Pronunciation | Note |
| A a | [a] | like "a" in "arc" |
| Б б | [b] | like "b" in "brother" |
| В в | [v] | like "v" in "vest" |
| Г г | [g] | like "g" in "go" |
| Д д | [d] | like "d" in "day" |
| Ѓ ѓ | [gy] | like "gy" in "gear" |
| E e | [e] | like "e" in "bed", or like "ea" in "head" |
| Ж ж | [zh] | like "s" in "pleasure", or "zh" in foreign names (Russian, Chinese, etc.) such as "Zhivago" |
| З з | [z] | like "z" in "zeal", or like "s" in "reason" |
| Ѕ ѕ | [dz] | like "ds" in "kids" |
| И и | [i] | like "e" in "he", or like "y" in "lorry", "factory" |
| J j | [y] | like "y" in yes" |
| К к | [k] | like "k" in "key", or like "c" in "cat" |
| Л л | [l] | like "l" in "love" |
| Љ љ | [ly] | like "ll" in "million", "brilliant", |
| М м | [m] | like "m" In "mother", "milk" |
| Н н | [n] | like "n" in "no", or "kn" in "knob" |
| Њ њ | [ny] | like "n" in "news", "onion" |
| О о | [o] | like "o" in "not", "hot", "spot" |
| П п | [p] | like "p" in "pot" |
| Р р | [r] | roiled, rhotic "r", like "r" in Scottish, Irish and some rural English dialects |
| С с | [s] | like "s" in "stop", or "ss" in "bless", or like "c" in "cell" |
| Т т | [t] | like "t" in "top", |
| Ќ ќ | [ky] | like "q" in "queue" |
| У у | [oo] | like "oo" in "food" |
| Ф ф | [f] | like "f" in "fast", or like "ph" in "photo" |
| Х х | [h] | like "h" in "huge", or like "ch" in "loch" |
| Ц ц | [ts] | like 'ts" in "cats" |
| Ч ч | [ch] | like "ch" in "church" |
| Џ џ | [j] | like "j" in "John", "jungle" |
| Ш ш | [sh] | like "sh" in "shy", or like "s" in "sure" |
* Learning Macedonian
* Introduction • The Alphabet • Common phrases
* Lessons
* Beginner level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Intermediate level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Advanced level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Special level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4
* Grammar
* Adjectives • Adverbs • Prepositions • Nouns • Verbs
# Mac OS X Tiger/Utilities

The Utilities folder (inside the Applications folder) includes a number of useful utilities that can be used to configure, monitor and maintain your Mac.

## Contents

* Activity Monitor
* AirPort Admin Utility
* AirPort Setup Assistant
* Audio MIDI Setup
* Bluetooth File Exchange
* ColorSync Utility
* Console
* DigitalColor Meter
* Directory Access
* Disk Utility
* Grab
* Grapher
* Installer
* Keychain Access
* Migration Assistant
* NetInfo Manager
* Network Utility
* OBDC Administrator
* Printer Setup Utility
* System Profiler
* Terminal
* VoiceOver Utility
# Mac OS X Tiger/Utilities/Terminal
## Introduction

OS X includes a bash, Bourne Again Shell, for taking advantage of its power Unix-like kernel Darwin. The bash shell was developed by Brian Fox in 1987 for the GNU Project, as a free, as in freedom, and improved terminal for using with Unix and Unix-like operating systems. The terminal is used by entering commands and their parameters in the form of text, with output also usually being text based. It's is comparable to Windows' MS-DOS prompt. More information about Unix can be found in the Guide to Unix.

## Useful Commands

man [command name] - Used by entering man and then the name of the command, who wish to know more about. It then displays the command's man page, which tells the user exactly what the command does and that additional parameters the user can specify. When it doubt use it!
ls - Lists the contents of the current directory
cd [directory] - Moves from the current directory to the specified path name.
ps -ax - Lists all the current active processes along with their process number
kill [number] - This can be used to force quit any process running on your system by entering the process number obtained by using ps -ax. Probably not a good idea to use it unless you know what you're quitting.
vi [Filename] - vi is the standard Unix text editor, however it would take another article to describe all it commands and how to use it. If you don't specify a file name a new file will be created.
pico - Another text editor, slightly more user friendly, but not as standard, as vi.
emacs - Another 'text editor' emacs has evolved to become almost and operating system in and of itself, again it would take another wikibook to describe all it's features and uses.
tar -parameters [Filename] - Tar, short for Tape Archive, is a bundling program than can also be used to compress or decompress files. Use -x or -c, as parameters, to extract or create a tar file. Further options can change the name of the tar file and the compression used.
mkdir - Creates a new folder
rmdir - Deletes a folder
rm - Deletes a file
# Mac OS X Tiger/Utilities/System Profiler

System profiler simply lists all hardware and software present on your Macintosh. You can simply select from the list of options in the left-hand window pane to choose what is displayed.
# Mac OS X Tiger/Utilities/Grab

Take screenshots the hard way!
It's just easier to press cmd-shift-3.
# Mac OS X Tiger/Utilities/Grapher

Grapher, an app that’s new in Tiger, is like your average high school graphing calculator on steroids. Not only can it create garden-variety 2D graphs, but also highly complex 3D ones, as well. Unlike most graphing calculators, the graphs that are created do not need to be functions. For example, one can enter as an equation $y^{2}=x^{3}-x$ and get the graph:
# Mac OS X Tiger/Utilities/Activity Monitor

Activity Monitor is a utility integrated into OS X that allows you to see what is happening within your computer - specifically in regard to your processor, hard disk, memory, and network. Activity Monitor lets you identify and administer the applications and processes running on your computer. It also allows you to observe CPU activity, as well as your use of your memory, disks, and network. The activity can be viewed in the program itself or an icon representation in the dock.

## Equivalents on other operating systems
### Windows

Windows Task Manager (only on Windows operating systems that are based on the NT architecture, such as Windows NT, Windows 2000, Windows XP, Windows Server 2003, Windows Vista)
# Macedonian/Beginner

These six beginner lessons are meant for people who have had limited or no contact with the Macedonian language, and have almost or absolutely no knowledge of the language whatsoever.

## Lesson 1

John starts learning Macedonian online after finding that he might be stationed there. (click for lesson 1)

## Lesson 2

John goes to his first class in New Jersey, where he is taught by his new teacher Slavica. (click for lesson 2)

## Lesson 3

John goes over some basic phrases in Macedonian with his fellow co-students. (click for lesson 3)

## Lesson 4

John learns about the grammar features in Macedonians, more specifically noun gender, and adjectives. (click for lesson 4)

## Lesson 5

John and the group encounter Macedonian verbs. (click for lesson 5)

## Lesson 6

John is preparing for the big test. (click for lesson 6)
* Learning Macedonian
* Introduction • The Alphabet • Common phrases
* Lessons
* Beginner level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Intermediate level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Advanced level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6
* Special level
* Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4
* Grammar
* Adjectives • Adverbs • Prepositions • Nouns • Verbs
# Introduction to Chemical Engineering Processes/Why use recycle?
## What Is Recycle?

Recycling is the act of taking one stream in a process and reusing it in an earlier part of the process rather than discarding it. It is used in a wide variety of processes.

### Uses and Benefit of Recycle

The use of recycle makes a great deal of environmental and economic sense, for the following reasons among others:
* Using recycled materials lets a company achieve a wider range of separations
This will be demonstrated in the next section. However, there is a trade off: the more dilute or concentrated you want your product to be, the lower the flow rate you can achieve in the concentrated or dilute stream.
* By using recycle, in combination with some sort of separation process, a company can increase the overall conversion of an equilibrium reaction.
You may recall from general chemistry that many reactions do not go to completion but only up to a certain point, because they are reversible. How far the reaction goes depends on the concentrations (or partial pressures for a gas) of the products and the reactants, which are related by the reaction stoichiometry and the equilibrium constant K. If we want to increase the amount of conversion, one way we can do this is to separate out the products from the product mixture and re-feed the purified reactants in to the reactor. By Le Chatlier's Principle, this will cause the reaction to continue moving towards the products.
* By using recycled materials, it is possible to recover expensive catalysts and reagents.
Catalysts aren't cheap, and if we don't try to recycle them into the reactor, they may be lost in the product stream. This not only gives us a contaminated product but also wastes a lot of catalyst.
* Because of the previous three uses, recycle can decrease the amount of equipment needed to get a process meet specifications and consumer demand.
For example, it may improve reaction conversion enough to eliminate the need for a second reactor to achieve an economical conversion.
* Recycle reduces the amount of waste that a company generates.
Not only is this the most environmentally sounds way to go about it, it also saves the company money in disposal costs.
* Most importantly, all of these things can save a company money.
By using less equipment, the company saves maintainence as well as capital costs, and probably gets the product faster too, if the proper analysis is made.
it is use to stop the wastage of the material
# Introduction to Chemical Engineering Processes/Unusual Units
## Standard vs. Actual Volume

When specifying the volume of a gas, the pressure and temperature must be specified because the volume of a gas depends strongly on both temperature and pressure (assuming that it is in an expandable container). In order to avoid specifying a different set of conditions for each measurement, an engineer can convert to standard temperature and pressure (typically 1 atm and 0oC) which is common to all measurements. This allows direct comparisons of volume measurements, but also requires that one convert back to the actual conditions present in the system before the value can be used.
The conversion that is used assumes that the gas is ideal, so that:
$PV=nRT$

### Conversion of volume to volume

We wish to compare a standard state to the actual state in the system. Let us consider the standard state (state "s") first. We have the ideal gas law for the standard state:
$P_{s}*V_{s}=n_{s}RT_{s}$
Now let us compare the standard state to the actual conditions in the system. The standard state conditions have been completely specified. The ideal gas law is assumed to hold in the actual system conditions as well:
$P_{a}V_{a}=n_{a}RT_{a}$
Divide this equation by the standard-state ideal gas law gives:
${\frac {P_{a}V_{a}}{P_{s}{V}_{s}}}={\frac {n_{a}RT_{a}}{n_{s}RT_{s}}}$
where a is actual and s is standard. If we assume that we want to compare the same number of moles of the substance between the standard and actual states, the following conversion between the states is obtained:
$V_{a}={\frac {P_{s}V_{s}}{T_{s}}}*{\frac {T_{a}}{P_{a}}}$
# Lucid Dreaming/Appendices/FAQ

* Lucid Dreaming Introduction | Dream Recall | Induction Techniques | Using | Glossary | Appendices | Further Reading
* Appendices Lucid Dreaming FAQ | Pedro's VILD documentation
r3m0t is currently attempting to obtain copyright permission to host the FAQ on this website. (The author's email isn't working, and that's a permanent error - "Unrouteable address"! This does not look good... r3m0t (cont) (talk) 20:10, 3 Apr 2004 (UTC))
Thanks for the interest in my FAQ, my current email is lars@eid.online.no I'm busy with my Graduation Examination Paper right now, but I have a more updated FAQ stored locally. I like what is taking form here, and I have decided to participate. So I will update the whole section here and at wikipedia as I find the time.
So long! Lars
Meanwhile, the web version can be found here: Lucid Dreaming FAQ — Frequently Asked Questions
# Lucid Dreaming/Authors

In alphabetical order:
* Evilshiznat has had a few lucid dreams.
* Kaycee (cont) (talk) is a natural-born lucid dreamer who upholds a practical view on most things.
* KirbyMeister has only had one lucid dream so far, re-organized the entire Appendices area, and is a total Spongebob freak.
* r3m0t (cont) (talk) (15) has only had a few lucid dreams so far, but has written most of the information in the wikibook.
* Sourcejedi has just come out of anonymous lurking to demonstrate his ruthless editing tendencies by trying to clean up someone else's botched rename. He also has far too brief lucid dreams.
* Tharenthel has had a few lucid dreams so far, and has done mostly reorganization.
* Xgamer4 has had many lucid dreams. He made (if you can call it that) the FAQ page, and monitors the page.
# HKDSE Geography/M2b

The coast is a dynamic zone where the interaction of the sea and land processes takes place. It can be divided into several zones. (can be omitted)
* The shore is the area between the highest and the lowest water level. It can be divided into backshore, foreshore and nearshore.
* backshore: between highest water level and high tide level
* foreshore: between high tide level and low tide level
* nearshore: between low tide level and lowest water level
* Offshore is the submerged area extending seaward from nearshore.