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gnu-cobol is available via the homebrew system. Open a terminal window from /Applications/Utilities/Terminal or use the keypress Command+Space and type "Terminal". If you do not have the homebrew system installed, add it by typing, or copying and pasting into your terminal: ruby -e &quo...

Interprocess communication allows programmers to communicate between different processes. For example let us consider we need to write an PHP application that can run bash commands and print the output. We will be using proc_open , which will execute the command and return a resource that we can com...

Uploaded files are available in request.files, a MultiDict mapping field names to file objects. Use getlist — instead of [] or get — if multiple files were uploaded with the same field name. request.files['profile'] # single file (even if multiple were sent) request.files.getlist('charts') # li...

An enumerations value in no way needs to be unique: #include <stdlib.h> /* for EXIT_SUCCESS */ #include <stdio.h> /* for printf() */ enum Dupes { Base, /* Takes 0 */ One, /* Takes Base + 1 */ Two, /* Takes One + 1 */ Negative = -1, AnotherZero /* Takes Negativ...

CROSS APPLY enables you to "join" rows from a table with collection of JSON objects stored in a column. Imagine that you have a Company table with a column that contains an array of products (ProductList column) formatted as JSON array. OPENJSON table value function can parse these values...

Detailed instructions on getting azure-active-directory set up or installed.

It is well known that you cannot use the same file for input and ouput in the same command. For instance, $ cat header.txt body.txt >body.txt doesn’t do what you want. By the time cat reads body.txt, it has already been truncated by the redirection and it is empty. The final result will be th...

On Julia, you can define more than one method for each function. Suppose we define three methods of the same function: foo(x) = 1 foo(x::Number) = 2 foo(x::Int) = 3 When deciding what method to use (called dispatch), Julia chooses the more specific method that matches the types of the argument...

JSON is a popular data interchange format. The most popular JSON library for Julia is JSON.jl. To install this package, use the package manager: julia> Pkg.add("JSON") The next step is to test whether the package is working on your machine: julia> Pkg.test("JSON") I...

JSON that has been encoded as a string can easily be parsed into a standard Julia type: julia> using JSON julia> JSON.parse("""{ "this": ["is", "json"], "numbers": [85, 16, 12.0], "and": [t...

The JSON.json function serializes a Julia object into a Julia String containing JSON: julia> using JSON julia> JSON.json(Dict(:a => :b, :c => [1, 2, 3.0], :d => nothing)) "{\"c\":[1.0,2.0,3.0],\"a\":\"b\",\"d\":null}" julia>...

The clauses in a SELECT have a specific order: SELECT ... FROM ... WHERE ... GROUP BY ... HAVING ... ORDER BY ... -- goes here LIMIT ... OFFSET ...; ( SELECT ... ) UNION ( SELECT ... ) ORDER BY ... -- for ordering the result of the UNION. SELECT ... GROUP_CONCAT(DISTINCT x ORDER B...

Classes have instance variable (dependencies), on which they call methods. Example taken from http://www.jamesshore.com/Blog/Dependency-Injection-Demystified.html for reference public class Example { private DatabaseThingie myDatabase; public Example() { myDatabase = new DatabaseTh...

This counts the number of lines in a big file with wc -l while simultaneously compressing it with gzip. Both run concurrently. tee >(wc -l >&2) < bigfile | gzip > bigfile.gz Normally tee writes its input to one or more files (and stdout). We can write to commands instead of fil...

Class Car ... ' Parameterless Constructor Public Sub Class_Initialize() distances_ = Array(0) End Sub ' Default initialization method that can be invoked without ' explicitly using the method name. Public Default Function Init(wheels) wheels_ = ...

Basic Syntax Julia's array comprehensions use the following syntax: [expression for element = iterable] Note that as with for loops, all of =, in, and ∈ are accepted for the comprehension. This is roughly equivalent to creating an empty array and using a for loop to push! items to it. result ...

Configuring the Primary Server Requirements: Replication User for replication activities Directory to store the WAL archives Create Replication user createuser -U postgres replication -P -c 5 --replication + option -P will prompt you for new password + option -c is for max...

Detailed instructions on getting embedded-linux set up or installed. ARM Versatile Express Emulation On Qemu Environment Introduction: Host ubuntu :- 12.04 Linux kernel version: linux-4.4 busybox version: 1.24.0 Cross compiler tool chain: arm-2014.05-29-arm-none-linux-gnueabi-i686-pc-linux gnu...

Enumeration types can also be declared without giving them a name: enum { buffersize = 256, }; static unsigned char buffer [buffersize] = { 0 }; This enables us to define compile time constants of type int that can as in this example be used as array length.

Detailed instructions on getting glsl set up or installed.