====== AWK - AWK Math Operations ======

===== Basic Math Operations =====

Assuming a file, **test2.txt** exists with following contents:

<file>
pens      10    1.99
pencils   20    3.99
staplers   5    8.99
rulers    12    2.50
</file>

----

Issue the following command:

<code awk>
awk '{print $1,"QTY: "$2,"PRICE: "$3,"TOTAL: "$2*$3}' test2.txt
</code>

returns:

<code>
pens QTY: 10 PRICE: 1.99 TOTAL: 19.9
pencils QTY: 20 PRICE: 3.99 TOTAL: 79.8
staplers QTY: 5 PRICE: 8.99 TOTAL: 44.95
rulers QTY: 12 PRICE: 2.50 TOTAL: 30
</code>

<WRAP info>
**NOTE:**  The total multiples fields $2 with $3.
</WRAP>

----

AWK supports the full range of arithmetic operators including:

^Operator^Details^
|+|Adds numbers together.|
|-|Subtracts.|
|*|Multiples.|
|/|Divides.|
|<nowiki>^</nowiki>|Performs exponential mathematics.|
|%|Gives the modulo (remainder).|
|++|Adds one to the value of a variable.|
|+=|Assigns the result of an addition operation to a variable.|
|--|Subtracts one from a variable.|
|-=|Assigns the result of a subtraction operation to a variable.|
|*=|Assigns the result of multiplication.|
|/=|Assigns the result of division.|
|%=|Assigns the result of a modulo operation.|

----

===== Using a Variable =====

<code awk>
awk '{x=x+$2} {print x}' test2.txt
</code>

returns:

<code>
10
30
35
47
</code>

<WRAP info>
**NOTE:**  This assigns a variable named x.

It has shown a running total and calculated an overall total of 47 items.

</WRAP>

----

===== Advanced Example Using a Variable =====

<code awk>
awk '{x=x+($2*$3)}{print $1,"QTY: "$2,"PRICE: "$3,"TOTAL: "$2*$3,"BAL: "x}' test2.txt
</code>

returns:

<code>
pens QTY: 10 PRICE: 1.99 TOTAL: 19.9 BAL: 19.9
pencils QTY: 20 PRICE: 3.99 TOTAL: 79.8 BAL: 99.7
staplers QTY: 5 PRICE: 8.99 TOTAL: 44.95 BAL: 144.65
rulers QTY: 12 PRICE: 2.50 TOTAL: 30 BAL: 174.65
</code>

<WRAP info>
**NOTE:**  This lists each record while assigning a total value and keeping a running balance.
</WRAP>

----