The TANH() function is used to calculate the hyperbolic trigonometric tangent of a given expression (angle).
Here is the syntax of the TANH() function.
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.
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 hyperbolic tangent values for the contents of the math.txt file using TANH() function as shown below.
grunt> tanh_data = foreach math_data generate (data), TANH(data);
The above statement stores the result in the relation named tanh_data. Verify the contents of the relation using the Dump operator as shown below.
grunt> Dump tanh_data; (5.0,0.9999092042625951) (16.0,0.9999999999999747) (9.0,0.999999969540041) (2.5,0.9866142981514303) (5.9,0.9999849909996685) (3.1,0.9959493584508665)