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We assume a file using ; as a column delimiter. Selecting a specific set of columns only requires a print statement. For instance, the following program selects the columns 3, 4 and 7 from its input: awk -F';' -v 'OFS=;' '{ print $3, $4, $7 }' It is as usual possible to more carefully choose lin...

Given a file using ; as a column delimiter. We compute the median of the values in the second column with the following program, written for GNU awk. The provided input is the list of grades of a student group: gawk -F';' '{ sample[NR] = $2 } END { asort(sample); if(NR % 2 == 1) { p...

If you want to use only part of a library, you can selectively import the library. For example: // Import only foo and bar. import 'package:lib1/lib1.dart' show foo, bar; // Import all names EXCEPT foo. import 'package:lib2/lib2.dart' hide foo;

Deferred loading (also called lazy loading) allows an application to load a library on demand, if and when it’s needed. To lazily load a library, you must first import it using deferred as. import 'package:deferred/hello.dart' deferred as hello; When you need the library, invoke loadLibrary() us...

For example we have WordCountService with countWords method: class WordCountService { def countWords(url: String): Map[String, Int] = { val sparkConf = new SparkConf().setMaster("spark://somehost:7077").setAppName("WordCount")) val sc = new SparkContext(sp...

class CustomException implements Exception { String cause; CustomException(this.cause); } void main() { try { throwException(); } on CustomException { print("custom exception is been obtained"); } } throwException() { throw new CustomException('This is m...

iex(1)> name = "John" "John" iex(2)> greeting = "Hello, #{name}" "Hello, John" iex(3)> num = 15 15 iex(4)> results = "#{num} item(s) found." "15 item(s) found."

Fortran originally was designed for a fixed format form based on an 80 column punched card: Yes: This is a line of the author's own code These were created on a card punch machine, much like this: Images are original photography by the author The format, as shown on the illustrated sample ca...

C99 Using the system header file stdbool.h allows you to use bool as a Boolean data type. true evaluates to 1 and false evaluates to 0. #include <stdio.h> #include <stdbool.h> int main(void) { bool x = true; /* equivalent to bool x = 1; */ bool y = false; /* equivalent t...

It is a good practice to provide expression string arguments as braced strings. The heading "Double Substitution" outlines important reasons behind the same. The expr command evaluates an operator-based expression string to calculate a value. This string is constructed from the arguments ...

To implement the equals method of an object easily you could use the EqualsBuilder class. Selecting the fields: @Override public boolean equals(Object obj) { if(!(obj instanceof MyClass)) { return false; } MyClass theOther = (MyClass) obj; EqualsBuilder builde...

To implement the hashCode method of an object easily you could use the HashCodeBuilder class. Selecting the fields: @Override public int hashCode() { HashCodeBuilder builder = new HashCodeBuilder(); builder.append(field1); builder.append(field2); builder.append(field3); ...

To implement the toString method of an object easily you could use the ToStringBuilder class. Selecting the fields: @Override public String toString() { ToStringBuilder builder = new ToStringBuilder(this); builder.append(field1); builder.append(field2); builder.append(field3...

When the view controller is presented within a tab bar controller, you can access the tab bar controller like this: Swift let tabBarController = viewController.tabBarController Objective-C UITabBarController *tabBarController = self.tabBarController; When the view controller is part on an n...

JavaScript has native conversion from Number to it's String representation for any base from 2 to 36. The most common representation after decimal (base 10) is hexadecimal (base 16), but the contents of this section work for all bases in the range. In order to convert a Number from decimal (base...

Parameters The first 4 parameters are passed in (in order) RCX, RDX, R8 and R9. XMM0 to XMM3 are used to pass floating point parameters. Any further parameters are passed on the stack. Parameters larger than 64bit are passed by address. Spill Space Even if the function uses less than 4 paramet...

If you want PHP to display runtime errors on the page, you have to enable display_errors, either in the php.ini or using the ini_set function. You can choose which errors to display, with the error_reporting (or in the ini) function, which accepts E_* constants, combined using bitwise operators. P...

Warning It is imperative that phpinfo is only used in a development environment. Never release code containing phpinfo into a production environment Introduction Having said that, it can be a useful tool in understanding the PHP environment (OS, configuration, versions, paths, modules) in which ...

C99 Added in the C standard version C99, _Bool is also a native C data type. It is capable of holding the values 0 (for false) and 1 (for true). #include <stdio.h> int main(void) { _Bool x = 1; _Bool y = 0; if(x) /* Equivalent to if (x == 1) */ { puts("T...

You can use gradle to have BuildConfig constants and res values on a per flavor basis. Just add the value to the flavor you want to support. android { defaultConfig { resValue "string", "app_name", "Full App" buildConfigField "boolean",...