FFT Example 3: 3D Signal - Teradata Vantage

Machine Learning Engine Analytic Function Reference

Product
Teradata Vantage
Release Number
8.00
1.0
Published
May 2019
Language
English (United States)
Last Update
2019-11-22
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blj1506016597986.ditamap
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B700-4003
lifecycle
previous
Product Category
Teradata Vantageā„¢

In this example, the signals are three-dimensional (3D).

Input

The input table has one time sequence of 3D signals of length 8, represented by this 2x2x2 matrix in the value1 column: ( ( (1, 2) (3, 4) ) ( (5, 6) (7, 8) ) )

InputTable: fft_input3
id1 timestep value1
1 1 1
1 2 2
1 3 3
1 4 4
1 5 5
1 6 6
1 7 7
1 8 8

SQL Call

CREATE MULTISET TABLE fft_output3 AS (
  SELECT * FROM FFT (
    ON fft_input3 AS inputtable PARTITION BY id1 ORDER BY timestep
    USING
    ValueColumns ('value1')
    NumDimensions (3)
  ) AS dt
) WITH DATA;

Output

fft_output_3
id1_0 timestep real_value1 imag_value1
1 1 36 0
1 2 -4 0
1 3 -8 0
1 4 0 0
1 5 -16 0
1 6 0 0
1 7 0 0
1 8 0 0