Apache Pig - ROUND()

The ROUND() function is used to get the value of an expression rounded to an integer (if the result type is float) or rounded to a long (if the result type is double).

grunt> ROUND()

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 generate round values of the contents of the math.txt file using ROUND() function as shown below.

grunt> round_data = foreach math_data generate (data), ROUND(data);

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

grunt> Dump round_data;
 
(5.0,5) 
(16.0,16) 
(9.0,9) 
(2.5,3) 
(5.9,6) 
(3.1,3)