Mathematica definitions

Load needed packages for this notebook

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Set up defaults

Turn off annoying warning messages
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Set default options for specific functions
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Visualization functions

Fix time variable for sampled signals
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Generate periodic waveform from one period

PeriodicSignal[f, {dmin, dmax}, {t, min, max}] generates a periodic waveform for the interval [min, max]. It is assumed that one period of the function f(t) is defined over the interval [dmin, dmax].

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Plot periodic waveforms

PeriodicPlot[f, {dmin, dmax}, {t, min, max}, opts] plots a a periodic waveform for the interval [min, max]. It is assumed that one period of the function f(t) is defined over the interval [dmin, dmax]. The 'opts' argument passed plotting options to the Mathematica function Plot[ ].

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Plot discrete-time signal as sequence of amplitude lines
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Filtering definitions

FourierRearrange[fft] rearranges the result of an FFT (Mathematica function Fourier[ ]), to a easier to visualize the spectrum represented by 'fft'. The length of the list 'fft' is assumed to be even; if it is not, the last term in 'fft' is dropped.

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Filter[n, sampleRate, {lowFreq, highFreq}] generates an ideal discrete filter for an FFT list of length 'n' (sampled at 'sampleRate'), with a bandpass from 'lowFreq' to 'highFreq' (in Hz).

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Converted by Mathematica      January 13, 2003