Hello everyone,
I’m trying to make an FFT of signal that I read from an ASCII file (y,t)
But I have a problem with the FFT! I even can’t run the example provided with root (FFT.C), I get an error message about libfftw3-3.dll.
I saw this post, but I didn’t know how to install fftw3-3. I’ve downloaded it, but what next?:
how to install FFTW3? and how to know if it’s in the path? if it is not, how can I set it?
I’m using root in windows !!!
Thank you in advance.
[quote=“Momos1989”]Hello everyone,
I’m trying to make an FFT of signal that I read from an ASCII file (y,t)
But I have a problem with the FFT! I even can’t run the example provided with root (FFT.C), I get an error message about libfftw3-3.dll.
I saw this post, but I didn’t know how to install fftw3-3. I’ve downloaded it, but what next?:
how to install FFTW3? and how to know if it’s in the path? if it is not, how can I set it?
Thank you in advance.[/quote]
I do not know what your system is, in principle, it’s quite easy to build libfftw from the source and specify
its location during configuration with --enable-fftw3 --with-fftw3-incdir=the_place_where_you_install --with-fftw3-libdir=…
Sorry but I didn’t understand your reply!
I’m using windows, and I’m a beginner with root.
Can you please give me the steps to follow in details.
Thank you for your reply. 
Hi everyone,
I installed root from source with cygwin. How can I install the fftw3 now??
Does anyone have an idea ??
I tried to type in command line:
–with-fftw3-incdir=“the directory where fftw3.h is”
–with-fftw3-libdir=“the directory where the fftw library is”
But I get the message No such file or directory!!! 
Thank you in advance.