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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...

When the shell performs parameter expansion, command substitution, variable or arithmetic expansion, it scans for word boundaries in the result. If any word boundary is found, then the result is split into multiple words at that position. The word boundary is defined by a shell variable IFS (Interna...

The NSString formatting supports all the format strings available on the printf ANSI-C function. The only addition made by the language is the %@ symbol used for formatting all the Objective-C objects. It is possible to format integers int myAge = 21; NSString *formattedAge = [NSString stringWith...

pat='[^0-9]+([0-9]+)' s='I am a string with some digits 1024' [[ $s =~ $pat ]] # $pat must be unquoted echo "${BASH_REMATCH[0]}" echo "${BASH_REMATCH[1]}" Output: I am a string with some digits 1024 1024 Instead of assigning the regex to a variable ($pat) we could als...

a='I am a simple string with digits 1234' pat='(.*) ([0-9]+)' [[ "$a" =~ $pat ]] echo "${BASH_REMATCH[0]}" echo "${BASH_REMATCH[1]}" echo "${BASH_REMATCH[2]}" Output: I am a simple string with digits 1234 I am a simple string with digits 1234

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_ = ...

SET TEST=0 IF %TEST% == 0 ( echo TEST FAILED ) ELSE IF %TEST% == 1 ( echo TEST PASSED ) ELSE ( echo TEST INVALID )

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.

Julia uses the standard mathematical meanings of arithmetic operations when applied to matrices. Sometimes, elementwise operations are desired instead. These are marked with a full stop (.) preceding the operator to be done elementwise. (Note that elementwise operations are often not as efficient as...

class ImageCreationExample { static Image createSampleImage() { // instantiate a new BufferedImage (subclass of Image) instance BufferedImage img = new BufferedImage(640, 480, BufferedImage.TYPE_INT_ARGB); //draw something on the image paintOnI...

We can just do simple replacement of separators from space to new line, as following example. echo $sentence | tr " " "\n" It'll split the value of the variable sentence and show it line by line respectively.

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...

ps -e | less ps -e shows all the processes, its output is connected to the input of more via |, less paginates the results.

Internal Table Declaration Based on Local Type Definition " Declaration of type TYPES: BEGIN OF ty_flightb, id TYPE fl_id, dat TYPE fl_date, seatno TYPE fl_seatno, firstname TYPE fl_fname, lastname TYPE fl_lname, fl...

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",...