Awk operators (Arithmetic Operators, value assignment operators, Relational operators, logical operators, and regular operators)

Reprinted: http://www.cnblogs.com/chengmo/archive/2010/10/11/1847515.html

 

As one of the excellent tools for text processing, awk has its own rich operators. The following is a summary of all operators. Can be divided into: Arithmetic Operators, value assignment operators, Relational operators, logical pre-Algorithm, Regular operator.

 

I. Introduction to operators

Operator	Description
Value assignment operator
= + =-= * =/= % = ^ = ** =	Assignment Statement
Logical operators
|	Logic or
&&	Logic and
Regular Operators
~ ~!	Match Regular Expressions and do not match Regular Expressions
Relational operators
<<=>>=! ===	Relational operators
Arithmetic Operators
+-	Add, subtract
*/&	Multiplication, division and remainder
+ -!	Mona1 addition, subtraction, and non-logical
^ ***	Power
++ --	Increase or decrease as a prefix or suffix
Other operators
$	Field Reference
Space	String Connector
? :	C-condition expression
In	Whether a key value exists in the array

 

Note: awk operators andC LanguageSame. Expressions and functions are basically the same

Ii. instance Introduction

• Awk assignment operator

A + = 5; equivalent to: a = a + 5; other similar

• Awk logical operators

[Chengmo @ localhost ~] $ Awk 'in in {A = 1; B = 2; print (A> 5 & B <= 2), (a> 5 | B <= 2 );}'
0 1

• Awk regular operators

[Chengmo @ localhost ~] $ Awk 'in in {A = "100 Testa"; if (~ /^ 100 */) {print "OK ";}}'
OK

• Awk Relational operators

For example:> <can be used for string comparison or numerical comparison. The key is that if the operand is a string, it is converted to string comparison. Both of them are numeric values. String comparison: compare strings in ASCII order.

[Chengmo @ localhost ~] $ Awk 'in in {A = "11"; if (a> = 9) {print "OK ";}}'

 

[Chengmo @ localhost ~] $ Awk 'in in {A = 11; if (a> = 9) {print "OK ";}}'
OK

• Awk Arithmetic Operators

It indicates that all operations are performed as arithmetic operators, the operands are automatically converted to numerical values, and all non-numeric values are changed to 0.

[Chengmo @ localhost ~] $ Awk 'in in {A = "B"; print a ++, ++ ;}'
0 2

• Other operators

? : Operator

[Chengmo @ localhost ~] $ Awk 'in in {A = "B"; print a = "B "? "OK": "Err ";}'
OK

 

In Operator

[Chengmo @ localhost ~] $ Awk 'in in {A = "B"; arr [0] = "B"; arr [1] = "C"; print (A in ARR );}'
0

 

[Chengmo @ localhost ~] $ Awk 'in in {A = "B"; arr [0] = "B"; arr ["B"] = "C"; print (A in ARR );}'
1

In operator to determine whether the key value exists in the array.