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DELIMITER $$ DROP PROCEDURE IF EXISTS sp_nested_loop$$ CREATE PROCEDURE sp_nested_loop(IN i INT, IN j INT, OUT x INT, OUT y INT, INOUT z INT) BEGIN DECLARE a INTEGER DEFAULT 0; DECLARE b INTEGER DEFAULT 0; DECLARE c INTEGER DEFAULT 0; WHILE a < i DO WHILE b <...

Clickjacking is a malicious technique of tricking a Web user into clicking on something different from what the user perceives they are clicking on. Learn more To enable clickjacking protection, add the XFrameOptionsMiddleware to your middleware classes. This should already be there if you didn...

In Java (and other languages), using null is a common way of indicating that there is no value attached to a reference variable. In Scala, using Option is preferred over using null. Option wraps values that might be null. None is a subclass of Option wrapping a null reference. Some is a subclass of...

A simple scatter plot import matplotlib.pyplot as plt # Data x = [43,76,34,63,56,82,87,55,64,87,95,23,14,65,67,25,23,85] y = [34,45,34,23,43,76,26,18,24,74,23,56,23,23,34,56,32,23] fig, ax = plt.subplots(1, figsize=(10, 6)) fig.suptitle('Example Of Scatterplot') # Create the Scatter P...

Shaded region below a line import matplotlib.pyplot as plt # Data x = [0,1,2,3,4,5,6,7,8,9] y1 = [10,20,40,55,58,55,50,40,20,10] # Shade the area between y1 and line y=0 plt.fill_between(x, y1, 0, facecolor="orange", # The fill color color='...

Send a 304 Not Modified response status from the server send in response to a client request that contains headers If-Modified-Since and If-None-Match, if the request resource hasn’t changed. For example if a client request for a web page includes the header If-Modified-Since: Fri, 22 Jul 2016 14:3...

Vim's standard search commands are / for forward search and ? for backward search. To start a search from normal mode: press /, type your pattern, press <CR> to perform the search. Examples: /foobar<CR> search forward for foobar ?foo\/bar<CR> search backward for ...

You can open a new split within Vim with the following commands, in normal mode: Horizontally: :split <file name> :new Vertically: :vsplit <file name> :vnew split will open the file in a new split at the top or left of your screen (or current split.) :sp and :vs are convenie...

ANTLR contains a testing tool in its runtime library, this tool can be used to display information detailing how the parsing is performed to match input against defined rules in your grammar file. To use this tool contained within the ANTLR jar file you should setup your systems classpath to allow ...

Lexer rules define token types. Their name has to start with an uppercase letter to distinguish them from parser rules. INTEGER: [0-9]+; IDENTIFIER: [a-zA-Z_] [a-zA-Z_0-9]*; OPEN_PAREN: '('; CLOSE_PAREN: ')'; Basic syntax: SyntaxMeaningAMatch lexer rule or fragment named AA BMatch A follow...

When tokens like '{' are used in a parser rule, an implicit lexer rule will be created for them unless an explicit rule exists. In other words, if you have a lexer rule: OPEN_BRACE: '{'; Then both of these parser rules are equivalent: parserRule: '{'; parserRule: OPEN_BRACE; But if the OPE...

Several lexer rules can match the same input text. In that case, the token type will be chosen as follows: First, select the lexer rule which matches the longest input If the text matches an implicitly defined token (like '{'), use the implicit rule If several lexer rules match the same input l...

A lexer action is a block of arbitrary code in the target language surrounded by {...}, which is executed during matching: IDENTIFIER: [A-Z]+ { log("matched rule"); }; A semantic predicate is a block of arbitrary code in the target language surrounded by {...}?, which evaluates to a bo...

In every applications life-cycle comes a day where it's components needs to be updated. Everyone knows the pain of updating every single dependency one-by-one. Well here you just need to issue the command: npm update (-g) If the "-g" is there then npm will update the global packages. ...

function assign(obj, prop, value) { if (typeof prop === 'string') prop = prop.split('.'); if (prop.length > 1) { var e = prop.shift(); assign(obj[e] = Object.prototype.toString.call(obj[e]) === '[object Object]' ? obj[e] ...

Here is an example of how to import a function that is defined in an unmanaged C++ DLL. In the C++ source code for "myDLL.dll", the function add is defined: extern "C" __declspec(dllexport) int __stdcall add(int a, int b) { return a + b; } Then it can be included into ...

""" ================================================================================ CREATE A 2 BY 2 GRID OF SUB-PLOTS WITHIN THE SAME FIGURE. ================================================================================ """ import matplotlib.pyplot as plt ...

""" ================================================================================ DRAW MULTIPLE LINES IN THE SAME PLOT ================================================================================ """ import matplotlib.pyplot as plt ...

JavaFX 8 The following example demonstrates how to add custom properties that can be styled from css to a custom Node. Here 2 DoublePropertys are added to the Rectangle class to allow setting the width and height from CSS. The following CSS could be used for styling the custom node: StyleableRe...

Objective-C supports a special type called `instancetype that can only be used as type returned by a method. It evaluates to the class of the receiving object. Consider the following class hierarchy: @interface Foo : NSObject - (instancetype)initWithString:(NSString *)string; @end @interf...