IFFT Example: 1D Signal | Teradata Vantage - IFFT Example: 1D Signal - Teradata Vantage

In this example, the signal is one-dimensional (1D).

Input

• InputTable: fft_output1, output by FFT Example: 1D Signal

SQL Call

CREATE MULTISET TABLE ifft_output_table1 AS (
  SELECT * FROM IFFT (
    ON fft_output1 AS InputTable PARTITION BY id_0 ORDER BY timestep
    USING
      TargetColumns ('real_value1', 'imag_value1')
      Dimensions (1)
      RealValuedSignal ('false')
  ) AS dt
) WITH DATA;

Output

SELECT * FROM ifft_output_table1;

 id_0 timestep real_real_value1 imag_real_value1       
 ---- -------- ---------------- ---------------------- 
    3        3              6.0                    0.0
    3        2              5.0  6.123233995736766E-17
    3        4              7.0 -6.123233995736766E-17
    3        1              4.0                    0.0
    1        1              1.0                    0.0
    2        2              3.0                    0.0
    2        1              2.0                    0.0

Download a zip file of all examples and a SQL script file that creates their input tables.