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What is Apache Pig - ACOS()?
- The ACOS() function of Pig Latin is used to calculate the arc cosine value of a given expression.
Syntax :
- Here is the syntax of the ACOS() function.
grunt> ACOS(expression)
Example
- Assume that there is a file named wikitechy_math.txt in the HDFSdirectory /pig_data/. This file contains integer and floating point values as shown below.
wikitechy_math.txt
3
10
15
6.5
4.9
7.5
- And, we have loaded this file into Pig with a relation named wikitechy_math_data as shown below.
grunt> wikitechy_math_data = LOAD 'hdfs://localhost:9000/pig_data/wikitechy_math.txt' USING PigStorage(',')
as (data:float);
- Let us now calculate the arc cosine values of the contents of the wikitechy_math.txt file using ACOS() function as shown below.
grunt> acos_data = foreach wikitechy_math_data generate (data), ACOS(data);
- The above statement stores the result in the relation named abs_data. Verify the contents of the relation using the Dump operator as shown below.
grunt> Dump acos_data;
Output:
(3.0,NaN)
(10.0,NaN)
(15.0,NaN)
(6.5,NaN)
(4.9,NaN)
(7.5,NaN)