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Initialize serial device import serial #Serial takes two parameters: serial device and baudrate ser = serial.Serial('/dev/ttyUSB0', 9600) to read single byte from serial device data = ser.read() to read given number of bytes from the serial device data = ser.read(size=5) to read one li...

In this exemple, we want to execute code which is stored in a string format. # the string str <- "1+1" # A string is not an expression. is.expression(str) [1] FALSE eval(str) [1] "1+1" # parse convert string into expressions parsed.str <- parse(text="1+1...

Instead of using regex, the Lua string library has a special set of characters used in syntax matches. Both can be very similar, but Lua pattern matching is more limited and has a different syntax. For instance, the character sequence %a matches any letter, while its upper-case version represents al...

This is an example on how to control PHP error logging in a virtual host site for development and debugging. Assumptions The PHP module has been installed. Development environment is not for production. <VirtualHost *:80> ServerName example.com DocumentRoot /var/www/domains/e...

string <- ' some text on line one; and then some text on line two ' Trimming Whitespace "Trimming" whitespace typically refers to removing both leading and trailing whitespace from a string. This may be done using a combination of the previous examples. gsub is used to for...

Creating a chart that displays a static dataset is relatively simple. For example, if we have this array of objects as the data: var data = [ {title: "A", value: 53}, {title: "B", value: 12}, {title: "C", value: 91}, {title: "D", value: 24...

Debian/Ubuntu # apt-get update & apt-get -y upgrade # apt-get install cron Fedora/CentOS # yum -y update # yum install vixie-cron Arch # pacman --noconfirm -Syu # pacman -S cronie

To get a list of available serial ports use python -m serial.tools.list_ports at a command prompt or from serial.tools import list_ports list_ports.comports() # Outputs list of available serial ports from the Python shell.

Add the debugger statement in your content script var foo = 1; debugger; foo = 2; Open the Developer Tool on the web page where your content script is injected to see the code execution pause at those lines.

HTML: <div ng-app="myApp" ng-controller="Controller"> <some-chart data="data"></some-chart> </div> Javascript: angular.module('myApp', []) .directive('someChart', function() { return { restrict: 'E', scope: {dat...

Below are some tips to remember while we are writing a select query in MySQL that can help us and reduce our query time:- Whenever we use where in a large table we should make sure the column in where clause are index or not. Ex:- Select * from employee where user_id > 2000. user_id if ind...

To get started with unit testing PowerShell code using the Pester-module, you need to be familiar with three keywords/commands: Describe: Defines a group of tests. All Pester test files needs at least one Describe-block. It: Defines an individual test. You can have multiple It-blocks inside a De...

Drawing text in canvas with your font from assets. Typeface typeface = Typeface.createFromAsset(getAssets(), "fonts/SomeFont.ttf"); Paint textPaint = new Paint(); textPaint.setTypeface(typeface); canvas.drawText("Your text here", x, y, textPaint);

Detailed instructions on getting axapta set up or installed.

Download the latest stable version from Activiti's website or you can check out the code from github and unzip to a directory of choice and then check out the readme.html that includes pointers to the docs and the release notes. The userguide ( docs/userguide/index.html ) includes instructions on ho...

Temporary tables could be very useful to keep temporary data. Temporary tables option is available in MySQL version 3.23 and above. Temporary table will be automatically destroyed when the session ends or connection is closed. The user can also drop temporary table. Same temporary table name can b...

Drop Temporary Table is used to delete the temporary table which you are created in your current session. DROP TEMPORARY TABLE tempTable1 DROP TEMPORARY TABLE IF EXISTS tempTable1 Use IF EXISTS to prevent an error occurring for tables that may not exist

Although Julia is not a purely functional language, it has full support for many of the cornerstones of functional programming: first-class functions, lexical scope, and closures. The fixed-point combinator is a key combinator in functional programming. Because Julia has eager evaluation semantics ...

The SKI combinator system is sufficient to represent any lambda calculus terms. (In practice, of course, lambda abstractions blow up to exponential size when they are translated into SKI.) Due to the simplicity of the system, implementing the S, K, and I combinators is extraordinarily simple: A Dir...

string is defined as alias string = immutable(char)[];: so need to use dup to make a mutable char array, before it can be reversed: import std.stdio; import std.string; int main() { string x = "Hello world!"; char[] x_rev = x.dup.reverse; writeln(x_rev); // !dlr...