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There is a 5th optional parameter, MinimumMagnitude. This parameter is used only if Polar=TRUE. All frequency components with magnitude less than MinimumMagnitude will be suppressed with a zero magnitude-phase entry. This is very useful when looking at the magnitude-phase spectrum of a signal because there is always some very tiny amount of rounding error when doing FFT algorithms and results in incorrect non-zero phase for non-existent frequencies. By providing a suitable value to this parameter, these non-existent frequency components can be suppressed. By default the value of this 5th parameter is 0.0, so *no* suppression is done by default.