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Environment.ProcessorCount Gets the number of logical processors on the current machine. The CLR will then schedule each thread to a logical processor, this theoretically could mean each thread on a different logical processor, all threads on a single logical processor or some other combination...

Sometimes, you want your threads to simultaneously share data. When this happens it is important to be aware of the code and lock any parts that could go wrong. A simple example of two threads counting is shown below. Here is some dangerous (incorrect) code: using System.Threading; class MainCl...

Everything between /* and */ is commented. void main() { for (int i = 0; i < 5; i++) { /* This is commented, and will not affect code */ print('hello ${i + 1}'); } }

Using a doc comment instead of a regular comment enables dartdoc to find it and generate documentation for it. /// The number of characters in this chunk when unsplit. int get length => ... You are allowed to use most markdown formatting in your doc comments and dartdoc will process it accor...

Processing tabular data with awk is very easy, provided that the input is correctly formatted. Most software producing tabular data use specific features of this family of formats, and awk programs processing tabular data are often specific to a data produced by a specific software. If a more gener...

Given a file using ; as a column delimiter. Permuting the first and the second column is accomplished by awk -F';' -v 'OFS=;' '{ swap = $2; $2 = $1; $1 = swap; print }'

Given a file using ; as a column delimiter. We compute the mean of the values in the second column with the following program, the provided input is the list of grades of a student group: awk -F';' '{ sum += $2 } END { print(sum / NR) }' <<EOF Alice;2 Victor;1 Barbara;1 Casper;4 Deborah;...

We assume a file using ; as a column delimiter. Selecting a specific set of columns only requires a print statement. For instance, the following program selects the columns 3, 4 and 7 from its input: awk -F';' -v 'OFS=;' '{ print $3, $4, $7 }' It is as usual possible to more carefully choose lin...

Given a file using ; as a column delimiter. We compute the median of the values in the second column with the following program, written for GNU awk. The provided input is the list of grades of a student group: gawk -F';' '{ sample[NR] = $2 } END { asort(sample); if(NR % 2 == 1) { p...

There are two main ways to create an axes in matplotlib: using pyplot, or using the object-oriented API. Using pyplot: import matplotlib.pyplot as plt ax = plt.subplot(3, 2, 1) # 3 rows, 2 columns, the first subplot Using the object-oriented API: import matplotlib.pyplot as plt fig = ...

Use import to specify how a namespace from one library is used in the scope of another library. import 'dart:html'; The only required argument to import is a URI specifying the library. For built-in libraries, the URI has the special dart: scheme. For other libraries, you can use a file system p...

If you import two libraries that have conflicting identifiers, then you can specify a prefix for one or both libraries. For example, if library1 and library2 both have an Element class, then you might have code like this: import 'package:lib1/lib1.dart'; import 'package:lib2/lib2.dart' as lib2; /...

If you want to use only part of a library, you can selectively import the library. For example: // Import only foo and bar. import 'package:lib1/lib1.dart' show foo, bar; // Import all names EXCEPT foo. import 'package:lib2/lib2.dart' hide foo;

Deferred loading (also called lazy loading) allows an application to load a library on demand, if and when it’s needed. To lazily load a library, you must first import it using deferred as. import 'package:deferred/hello.dart' deferred as hello; When you need the library, invoke loadLibrary() us...

iex(1)> name = "John" "John" iex(2)> greeting = "Hello, #{name}" "Hello, John" iex(3)> num = 15 15 iex(4)> results = "#{num} item(s) found." "15 item(s) found."

C99 Using the system header file stdbool.h allows you to use bool as a Boolean data type. true evaluates to 1 and false evaluates to 0. #include <stdio.h> #include <stdbool.h> int main(void) { bool x = true; /* equivalent to bool x = 1; */ bool y = false; /* equivalent t...

C of all versions, will effectively treat any integer value other than 0 as true for comparison operators and the integer value 0 as false. If you don't have _Bool or bool as of C99 available, you could simulate a Boolean data type in C using #define macros, and you might still find such things in...

There are 2 ways of instantiating prefabs: during design time or runtime. Design time instantiation Instantiating prefabs at design time is useful to visually place multiple instances of the same object (e.g. placing trees when designing a level of your game). To visually instantiate a prefab...

To implement the toString method of an object easily you could use the ToStringBuilder class. Selecting the fields: @Override public String toString() { ToStringBuilder builder = new ToStringBuilder(this); builder.append(field1); builder.append(field2); builder.append(field3...

When the view controller is presented within a tab bar controller, you can access the tab bar controller like this: Swift let tabBarController = viewController.tabBarController Objective-C UITabBarController *tabBarController = self.tabBarController; When the view controller is part on an n...