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What is TANH() function?
- Tanh is the hyperbolic tangent function, which is the hyperbolic analogue of the Tan circular function used throughout trigonometry.
- Tanh[α] is defined as the ratio of the corresponding hyperbolic sine and hyperbolic cosine functions via .
- Tanh may also be defined as , where is the base of the natural logarithm Log.
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TANH() function in Apache Pig
- The TANH() function is used to calculate the hyperbolic trigonometric tangent of a given expression (angle).
Syntax
grunt> TANH(expression)
Example
- Ensure that we have a file named wikitechy_math.txt in the HDFS directory /pig_data/. This file contains integer and floating point values as given below.
wikitechy_math.txt
5
16
9
2.5
5.9
3.1
- We have loaded this file into Pig with a relation named wikitechy_math_data as given below.
grunt> math_data = LOAD 'hdfs://localhost:9000/pig_data/wikitechy_math.txt' USING PigStorage(',')
as (data:float);
- Now you can generate the hyperbolic tangent values for the contents of the wikitechy_math.txt file using TANH() function as given below.
grunt> tanh_data = foreach math_data generate (data), TANH(data);
Verification
- Verify the contents of the relation using the Dump operator as given below.
grunt> Dump tanh_data;
Output
- The above statement stores the result in the relation named 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)