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POST requests are made with the request.post() method. If you need to send a web form request as a POST body, pass in a dictionary with key-value pairs as the data argument; requests will encode these to a application/x-www-form-urlencoded mimetype body: r = requests.post('https://github.com/', d...

The requests module has top-level functions for most HTTP methods: r = requests.put('https://example.com/', data=put_body) r = requests.delete('https://example.com/') r = requests.head('https://example.com/') r = requests.options('https://example.com/') r = requests.patch('https://example.com/'...

Docker volumes are not automatically removed when a container is stopped. To remove associated volumes when you stop a container: docker rm -v <container id or name> If the -v flag is not specified, the volume remains on-disk as a 'dangling volume'. To delete all dangling volumes: docker ...

K&R void* is a catch all type for pointers to object types. An example of this in use is with the malloc function, which is declared as void* malloc(size_t); The pointer-to-void return type means that it is possible to assign the return value from malloc to a pointer to any other type of ob...

+ dictionaryWithCapacity: Creates and returns a mutable dictionary, initially giving it enough allocated memory to hold a given number of entries. NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithCapacity:1]; NSLog(@"%@",dict); - init Initializes a newly allocated mut...

- removeObjectForKey: Removes a given key and its associated value from the dictionary. NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithDictionary:@{@"key1":@"Easy",@"key2": @"Tutorials"}]; [dict removeObjectForKey:@"key1"]; NSLog...

A declaration introduces an identifier and describes its type, be it a type, object, or function. A declaration is what the compiler needs to accept references to that identifier. These are declarations: extern int bar; extern int g(int, int); double f(int, double); /* extern can be omitted for f...

NetLogo is available for Windows, Mac, and Linux machines, downloadable from the project homepage. Windows Installer: NetLogo runs on Windows 10, Windows 8, Windows 7 and Vista. NetLogo 5.2.1 was the last version to support Windows XP and Windows 2000. Mac: Mac OS X 10.8.3 or newer is requ...

The InputRange concept has three functions, example: struct InputRange(T) { @property bool empty(); @property T front(); void popFront(); } In short, a way to check if the range is empty get the current element move to the next element To make our own type a InputRange, w...

To create a build target producing an executable, one should use the add_executable command: add_executable(my_exe main.cpp utilities.cpp) This creates a build target, e.g. make my_exe for GNU make, with the appropriate invocations of the configured compiler to pr...

(Select, one-to-one) As with ActionBlock, TransformBlock<TInput, TOutput> enables the execution of a delegate to perform some action for each input datum; unlike with ActionBlock, this processing has an output. This delegate can be a Func<TInput, TOutput>, in which case processing of t...

(SelectMany, 1-m: The results of this mapping are “flattened”, just like LINQ’s SelectMany) TransformManyBlock<TInput, TOutput> is very similar to TransformBlock<TInput, TOutput>. The key difference is that whereas a TransformBlock<TInput, TOutput> produces one and only one outpu...

(FIFO Queue: The data that comes in is the data that goes out) In short, BufferBlock provides an unbounded or bounded buffer for storing instances of T. You can “post” instances of T to the block, which cause the data being posted to be stored in a first-in-first-out (FIFO) order by the block. Yo...

Dim sites() As String = {"Stack Overflow", "Super User", "Ask Ubuntu", "Hardware Recommendations"} Dim query = From x In sites Select x.Length ' result = 14, 10, 10, 24 Query...

Dim sites() As String = {"Stack Overflow", "Super User", "Ask Ubuntu", "Hardware Recommendations"} Dim query = From x In sites Order By x.Length ' result = &qu...

Primary Constructor In Scala the primary constructor is the body of the class. The class name is followed by a parameter list, which are the constructor arguments. (As with any function, an empty parameter list may be omitted.) class Foo(x: Int, y: String) { val xy: String = y * x /* now...

A stream is an object that provides a low-level means to transfer data. They themselves do not act as data containers. The data that we deal with is in form of byte array(byte []). The functions for reading and writing are all byte orientated, e.g. WriteByte(). There are no functions for dealing w...

Java and most other languages store negative integral numbers in a representation called 2's complement notation. For a unique binary representation of a data type using n bits, values are encoded like this: The least significant n-1 bits store a positive integral number x in integral representati...

If we try to change an object on the UI thread from a different thread we will get a cross-thread operation exception: Private Sub Button_Click(sender As Object, e As EventArgs) Handles MyButton.Click ' Cross thread-operation exception as the assignment is executed on a different thread '...

Random and ThreadLocalRandom are good enough for everyday use, but they have a big problem: They are based on a linear congruential generator, an algorithm whose output can be predicted rather easily. Thus, these two classes are not suitable for cryptographic uses (such as key generation). One can ...