Tutorial by Examples: o

The following code has undefined behavior: char buffer[6] = "hello"; char *ptr1 = buffer - 1; /* undefined behavior */ char *ptr2 = buffer + 5; /* OK, pointing to the '\0' inside the array */ char *ptr3 = buffer + 6; /* OK, pointing to just beyond */ char *ptr4 = buffer + 7; /* un...

While there are many different control sequences for io:format and io_lib:format, most of the time you'll use only three different ones: ~s, ~p and ~w. ~s The ~s is for strings. It prints strings, binaries and atoms. (Anything else will cause a badarg error.) It doesn't quote or escape anything...

PHP's runtime memory limit is set through the INI directive memory_limit. This setting prevents any single execution of PHP from using up too much memory, exhausting it for other scripts and system software. The memory limit defaults to 128M and can be changed in the php.ini file or at runtime. I...

An extension to PHP called Xdebug is available to assist in profiling PHP applications, as well as runtime debugging. When running the profiler, the output is written to a file in a binary format called "cachegrind". Applications are available on each platform to analyze these files. To...

for /r command can be used to recursively visit all the directories in a directory tree and perform a command. @echo off rem start at the top of the tree to visit and loop though each directory for /r %%a in (.) do ( rem enter the directory pushd %%a echo In directory: cd rem leave...

If you are inside a folder of a git repository it might be nice to show the current branch you are on. In ~/.bashrc or /etc/bashrc add the following (git is required for this to work): function prompt_command { # Check if we are inside a git repository if git status > /dev/null 2>&a...

There are many cases when one has created an NSDate from only an hour and minute format, i.e: 08:12 The downside for this situation is that your NSDate is almost completely "naked" and what you need to do is to create: day, month, year, second and time zone in order to this object to &quo...

If ww have NSDate object, and we want to convert it into NSString. There are different types of Date strings. How we can do that?, It is very simple. Just 3 steps. Create NSDateFormatter Object NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; Set the date format in whi...

NSAttributedString (and its mutable sibling NSMutableAttributedString) allows you to create strings that are complex in their appearance to the user. A common application is to use this to display a string and adding custom kerning / letter-spacing. This would be achieved as follows (where label ...

NSMutableAttributedString *attributeString = [[NSMutableAttributedString alloc] initWithString:@"Your String here"]; [attributeString addAttribute:NSStrikethroughStyleAttributeName value:@2 range:NSMakeRange(0, [attributeString length])];

The return method only returns from the lambda, not the outer method. Beware that this is different from Scala and Kotlin! void threeTimes(IntConsumer r) { for (int i = 0; i < 3; i++) { r.accept(i); } } void demo() { threeTimes(i -> { System.out.println(i); return...

The package mmand provides functions for the calculation of Mathematical Morphologies for n-dimensional arrays. With a little workaround, these can also be calculated for raster images. library(raster) library(mmand) r <- raster("C:/Program Files/R/R-3.2.3/doc/html/logo.jpg") plot...

If you know the format of the string you are converting (parsing) you should use DateTime.ParseExact Dim dateString As String = "12.07.2003" Dim dateFormat As String = "dd.MM.yyyy" Dim dateValue As Date dateValue = DateTime.ParseExact(dateString, dateFormat, Globalization.C...

Simply use the .ToString overload of a DateTime object to get the format you require: Dim dateValue As DateTime = New DateTime(2001, 03, 06) Dim dateString As String = dateValue.ToString("yyyy-MM-dd") '2001-03-06

To start, import the zipfile module, and set the filename. import zipfile filename = 'zipfile.zip' Working with zip archives is very similar to working with files, you create the object by opening the zipfile, which lets you work on it before closing the file up again. zip = zipfile.ZipFile(fi...

Example of declarations are: int a; /* declaring single identifier of type int */ The above declaration declares single identifier named a which refers to some object with int type. int a1, b1; /* declaring 2 identifiers of type int */ The second declaration declares 2 identifiers named a1 a...

The following uses a variable with a for loop to rename a group of files. SetLocal EnableDelayedExpansion for %%j in (*.*) do ( set filename=%%~nj set filename=!filename:old=new! set filename=Prefix !filename! set filename=!filename! Suffix ren "%%j" "!filename!%%~x...

By default, the tooltip will appear on top of the element. We can use data-placement attribute to set the position of the tooltip on top, bottom, left or the right side of the element. <a href="#" data-toggle="tooltip" data-placement="top" title="Top tooltip&q...

Sometimes you need to call a Tcl command from your expression. For example, supposing you need the length of a string in it. To do that, you just use a [...] sequence in the expression: set halfTheStringLength [expr { [string length $theString] / 2 }] You can call any Tcl command this way, but i...

Create an .html file containing this snippet: <!DOCTYPE html> <meta charset="utf-8"> <body> <script src="//d3js.org/d3.v4.min.js"></script> <script> d3.select("body").append("span") .text("Hello, world!&quo...