FFT what does it mean?

A Fast Fourier Transform or FFT is an algorithm that samples a signal over space (period of time) and divides it into its frequency components. The FFT is a fast implementation of the DFT (discrete Fourier transform), computational complexity is reduced by applying the FFT algorithm to a signal.

The FFT can simply be used to characterise the magnitude and phase of a signal, or it can be used in combination with other operations to perform computations such as convolution and correlation.

Calculating the FFT of any time domain history curve in OnScale Post-process GUI

  1. Open you "XX.flxhst" data file which contains Time History Curve results from within OnScale Post-processor GUI
  2. Click one time only on the "functimefunc_1" time history curve (or any other curve)
  3. Click on the "FFT Record" function which then becomes activated
  4. Double click on the "functimefunc_1.amp" which then appears under Frequency History to display the amplitude of the Impedance curve 


Note: To open 2 windows like in this pictures, you will need to click on "Configure the Viewport" and change the view display.