?
No it is not useless, because all FFT algorithms
have errors because necessarily the precision of the floating point arithmetic
is finite. There are many such FFT algorithms all based of discrete Fourier
transformation. The computation yielding transformation from time domain to
frequency domain - the spectrum- requires complex number arithmetic thus one has
so tos speak a double limitation?due to?finite precision of floating
point arithmetic. Especially a pure sine has a very narrow Fourier integral thus
requires precision far above the precision of a for ex. double variable
type.
?
?
?
----- Original Message -----
Sent: Tuesday, December 17, 2013 7:28
PM
Subject: Re: [LTspice] Re: FFT
Resolution
?
Good Day? John?
I
am a simple soul? ( BTW maybe we are both Brits )
If
one conducts an FFT on a pure sinewave in theory there should be a single
spike of infinite height and zero width.? The more the spike departs from
those unattainable ideals shows the accuracy of the process.?
What
I have seen in LTPSPICE is far off and essentially useless?
I
hope to be shown the errors of my ways
