Tutorial by Examples: v

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...

If you store a list of tags in a row as coma separated values, STRING_SPLIT function enables you to transform list of tags into a table of values. CROSS APPLY enables you to "join" values parsed by STRING_SPLIT function with a parent row. Imagine that you have a Product table with a colu...

Quotes will be output as-is: echo "Some Text" "Some Text" Comment tokens are ignored: echo Hello World REM this is not a comment because it is being echoed! Hello World REM this is not a comment because it is being echoed! However, echo will still output var...

These two properties work in a similar fashion as the overflow property and accept the same values. The overflow-x parameter works only on the x or left-to-right axis. The overflow-y works on the y or top-to-bottom axis. HTML <div id="div-x"> If this div is too small to displa...

public static void saveImage(String destination) throws IOException { // method implemented in "Creating a simple image Programmatically and displaying it" example BufferedImage img = createSampleImage(); // ImageIO provides several write methods with different outputs ...

Create a simple DataFrame. import numpy as np import pandas as pd # Set the seed so that the numbers can be reproduced. np.random.seed(0) df = pd.DataFrame(np.random.randn(5, 3), columns=list('ABC')) # Another way to set column names is "columns=['column_1_name','column_2_name','c...

A for loop iterates from the starting value down to the ending value inclusive, as a "count-down" example. program CountDown; {$APPTYPE CONSOLE} var i : Integer; begin for i := 10 downto 0 do WriteLn(i); end. Output: 10 9 8 7 6 5 4 3 2 1 0

In order to avoid a divide by zero with a numberSet (what you get after a reduction like avg()) you can short-circuit the logic: $five = min(q("sum:rate{counter,,1}:haproxy.frontend.hrsp{}{status_code=5xx}", "1h", "")) $two = avg(q("sum:rate{counter,,1}:haproxy.f...

With series operations, things are dropped from the left side if there is no corresponding timestamp/datapoint in the right side. You can mix this with the dropbool function to avoid divide by zero: $five = q("sum:rate{counter,,1}:haproxy.frontend.hrsp{}{status_code=5xx}", "1h",...

Creating a WebM video from canvas frames and playing in canvas, or upload, or downloading. Example capture and play canvas name = "CanvasCapture"; // Placed into the Mux and Write Application Name fields of the WebM header quality = 0.7; // good quality 1 Best < 0.7 ok to poor fps =...

The ServiceLoader is a simple and easy to use built-in mechanism for dynamic loading of interface implementations. With the service loader - providing means for instantation (but not the wiring) - a simple dependency injection mechanism can be built in Java SE. With the ServiceLoader interface and ...

Code class Program { static void Main(string[] args) { int a = 20; Console.WriteLine("Inside Main - Before Callee: a = {0}", a); Callee(a); Console.WriteLine("Inside Main - After Callee: a = {0}", a); Console.WriteLine(); ...

Some "classic" Prolog textbooks still use the confusing and error-prone failure-driven loop syntax where a fail construct is used to force backtracking to apply a goal to every value of a generator. For example, to print all numbers up to a given limit: fdl(X) :- between(1,X,Y), print(Y),...

BufferedImage image = new BufferedImage(256, 256, BufferedImage.TYPE_INT_ARGB); //you don't have to use the Graphics object, you can read and set pixel color individually for (int i = 0; i < 256; i++) { for (int j = 0; j < 256; j++) { int alpha = 255; //don't forget this, or ...

Let's say we have a table team_person as below: +======+===========+ | team | person | +======+===========+ | A | John | +------+-----------+ | B | Smith | +------+-----------+ | A | Walter | +------+-----------+ | A | Louis | +------+-----------+ | C | ...

A VIEW acts very much like a table. Although you can UPDATE a table, you may or may not be able to update a view into that table. In general, if the SELECT in the view is complex enough to require a temp table, then UPDATE is not allowed. Things like GROUP BY, UNION, HAVING, DISTINCT, and some su...

PHP 5.4+ comes with a built-in development server. It can be used to run applications without having to install a production HTTP server such as nginx or Apache. The built-in server is only designed to be used for development and testing purposes. It can be started by using the -S flag: php -S &lt...

The most important thing for speeding up a query on any non-tiny table is to have a suitable index. WHERE a = 12 --> INDEX(a) WHERE a > 12 --> INDEX(a) WHERE a = 12 AND b > 78 --> INDEX(a,b) is more useful than INDEX(b,a) WHERE a > 12 AND b > 78 --> INDEX(a) or INDE...

This example has two parts - some boilerplate steps for adding Castle Windsor to your WCF service, and then a simple, concrete example to show how we configure and use Windsor's container. That makes the example a little bit long. If you already understand using a DI container then you likely only ...