I want to plot the data from an fft, however as the source data is very large consequently my fft data consists of one million samples. I want to plot the data in a log-log plot, but of course not all of the samples are necessary.
How can I downsample / reduce the number of samples/frequencies of the fft result while keeping the quality of the plot? If I remove for example every 4th sample it won't have an effect on the high frequencies, but I will lose precious samples on the low frequency range.
Thanks for your help!
To make it a bit more clear: The fft results have a sampling rate of 100Hz: 100Hz, 200Hz, 300Hz,...1e8Hz When I plot the spectrum logarithmically the range between 100 and 1000Hz has 9 samples (ok) between 1000 and 10000Hz has 90 samples (ok) between 10000 and 100000Hz has 900 samples (still ok, starts getting too much) between 1e7 and 1e8Hz has 900000 samples (way too much)
So I want to reduce the number of samples, especially in the higher frequencies, while keeping the low frequencies more intact, as a strong reduction of samples will change the plot significantly.