Apache Pig - CBRT()


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The CBRT() function of Pig Latin is used to calculate the cube root of a given expression.

Syntax

Here is the syntax of the CBRT() function.

grunt> CBRT(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 cube root values of the contents of the math.txt file using CBRT() function as shown below.

grunt> cbrt_data = foreach math_data generate (data), CBRT(data);

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

grunt> Dump cbrt_data;
 
(5.0,1.709975946676697) 
(16.0,2.5198420997897464) 
(9.0,2.080083823051904) 
(2.5,1.3572088082974532) 
(5.9,1.8069688790571206) 
(3.1,1.4580997208745365) 
apache_pig_math_functions.htm
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