fft Function

Performs a Fast Fourier Transform on supplied vector. The number of points used is the next binary power higher than the length of argument 1.

Arguments

Number Type Compulsory Default Description
1 real array Yes vector
2 string No 'Hanning' window function

Argument 2

Values are either 'Hanning' (default) or 'None'.

Returns

Return type: complex array

Notes

User's should note that using this function applied to raw transient analysis data will not produce meaningful results as the values are unevenly spaced. If you apply this function to simulation data, you must either specify that the simulator outputs at fixed intervals (select the Output at .PRINT step option in the Simulator > Choose Analysis... dialog box) or you must interpolate the results using the Interp function. The FFT plotting menu items run a script which interpolate the data if it detects that the results are unevenly spaced. Use of these menus does not require special consideration by the user.