Apache Pig - SQRT()


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The SQRT() function is used to calculate the square root of a given expression.

Syntax

Here is the syntax of the SQRT() function.

grunt> SQRT(expression)

Example

Assume that there is a file named math.txt in the HDFS directory /pig_data/. This file contains integer and floating point values as shown below.

math.txt

5 
16 
9 
2.5 
5.9 
3.1 

And, we have loaded this file into Pig with a relation named math_data as shown below.

grunt> math_data = LOAD 'hdfs://localhost:9000/pig_data/math.txt' USING PigStorage(',')
   as (data:float);

Let us now calculate the square root values of the contents of the math.txt file using SQRT() function as shown below.

grunt> sqrt_data = foreach math_data generate (data), SQRT(data);

The above statement stores the result in the relation named sqrt_data. Verify the contents of the relation using the Dump operator as shown below.

grunt> Dump sqrt_data;
  
(5.0,2.23606797749979) 
(16.0,4.0) 
(9.0,3.0) 
(2.5,1.5811388300841898) 
(5.9,2.4289915799292987) 
(3.1,1.76068165908337) 
apache_pig_math_functions.htm
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