The spec command will create a new plot consisting of the Fourier transforms of the vectors given on the command line.
spec start_freq stop_freq step_freq vector [...]This is based on a SPICE3 spec command by Anthony Parker of Macquarie University in Sydney Australia, which is available as part of the patch set from
The command will create a new plot consisting of the Fourier transforms of the vectors given on the command line. Each vector given should be a transient analysis result, i.e., have time as a scale, and each should have the same time scale. The Fourier transform will be computed using the frequency parameters given, and will use a window function as given with the specwindow variable.
The following variables control operation of the spec command. Each can be set with the set command, or equivalently from the Fourier tab of the Commands tool.
bartlet | Bartlet (triangle) window |
blackman | Blackman order 2 window |
cosine | Hanning (cosine) window |
gaussian | Gaussian window |
hamming | Hamming window |
hanning | Hanning (cosine) window |
none | No windowing |
rectangular | Rectangular window |
triangle | Bartlet (triangle) window |