FFT freq to time

Description FFT freq to time, inverse fft of "data"   Performs an inverse transform of a plot called data. See FFT time to freq Hot Key  none Script freqtotime data plot data Example Perform FFT time to freq using the example below, then use this freq to time function to invert the FFT and compare results. See also fftinit.

FFT time to freq

Description FFT time to freq, plots the real and imaginary components   Performs a time to frequency discrete Fourier transform. The results are plotted using formated strings to identify the plots. The complex result is saved in a plot named data. The data plot is the default name used for the inverse transform. If FFTinit hasn't been specified, a radix of 12 (4096 points) is used to initilaize the sine-cosine tables. See also fftinit, freqtotime and timetofreq. Hot Key  none Script * FFT time to freq, plots mag in db and phase timetofreq(current) alias previous = current temp = re(current) plotf temp re(fft(%s)) previous temp = im(previous) plotf temp im(fft(%s)) previous data = previous Example Open scope and paste this script into the command window. Then press <Ctrl + R> to plot a sine wave Select "FFT time to freq" from the Complex menu to view the result. set units = rad pi =4*atan(1) numpoints = 1000 time = (vector(numpoints)/(numpoints-1)*1m) newplot sineplot time setplot sineplot y = sin(2*pi*time*1k) y = y + sin(2*pi*time*3k)/3 y = y + sin(2*pi*time*5k)/5 plot y homecursors set units = deg

FFT time to mag

Description FFT magnitude   Performs a time to frequency discrete Fourier transform. The magnitude is computed and plotted using a formatted vector name. Hot Key  f Script timetofreq(current) temp = mag(current) plotf temp mag(fft(%s)) current Example Use the script from the above example

Wavelet time to wave

Description wave to time using daub4 wave function, use fftinit to set the wave space, default is 4096 points   See also timetowave command Hot Key  none Script timetowave current plot current Example Open scope and paste this script into the command window. Then press <Ctrl + R> to plot the "square: wave Select "Wavelet time to wave" from the Complex menu to view the result. Notice that the waveplot_t plot is used to hold the transform results. Wave space is real, there isn't a complex part. set units = rad pi =4*atan(1) numpoints = 1000 time = (vector(numpoints)/(numpoints-1)*10m) newplot waveplot time setplot waveplot y = sin(2*pi*time*1k) y = y + sin(2*pi*time*3k)/3 y = y + sin(2*pi*time*5k)/5 y = y * (1 - cos(2*pi*time/10m)) plot y homecursors set units = deg

Wavelet wave to time

Description wave to time using daub4 wave function, use fftinit to set the wave space, default is 4096 points   Performs and Inverse wavelet transform. See also wavetotime command. Hot Key  none Script wavetotime current plot current Example Perform the above example, the use this script to invert the result.