# Fatal error: fftw3.h: No such file or directory

**URL:** <https://discourse.channelflow.ch/t/fatal-error-fftw3-h-no-such-file-or-directory/165>\
**Category:** Installation\
**Created:** [April 13, 2022, 6:55pm UTC](https://discourse.channelflow.ch/t/fatal-error-fftw3-h-no-such-file-or-directory/165 "2022-04-13T18:55:04Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![chihin](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.channelflow.ch/chihin/32/26_2.png) [@chihin](https://discourse.channelflow.ch/u/chihin)\
**Post date:** [April 13, 2022, 6:55pm UTC](https://discourse.channelflow.ch/t/fatal-error-fftw3-h-no-such-file-or-directory/165/1 "2022-04-13T18:55:04Z")

</div>

Hi all, I’m having trouble installing channelflow. I’ve run cmake succesfully, cmake log in the last section.

However, I get the following error when I run make install -j 8

fatal error: fftw3.h: No such file or directory  
21 | #include \<fftw3.h\>  
| ^ ~~~~~~~~  
compilation terminated.

* * *

## – configuring channelflow version 2.0.2 – Using GNU compiler options

## – Starting system introspection – Found FFTW – FFTW\_LIBRARY=/usr/lib/x86\_64-linux-gnu/libfftw3.so – FFTW\_OMP\_LIBRARY=FFTW\_OMP\_LIBRARY-NOTFOUND – FFTW\_MPI\_LIBRARY=/usr/lib/x86\_64-linux-gnu/libfftw3\_mpi.so – MPI libs: – FFTW\_MPI library: /usr/lib/x86\_64-linux-gnu/libfftw3\_mpi.so – NetCDF include dir: /opt/anaconda3/include

– Include directories:  
– Git revision e9209c9e71db8561bac719244603e8d817e05fc5  
– Could NOT find Doxygen (missing: DOXYGEN\_EXECUTABLE)

###############################################  
########### Configuration summary ###########  
###############################################  
Compiler: GNU 9.3.0  
Build type: release  
Install prefix: /usr/include  
Building shared library: yes  
Linking programs to: shared library

Libraries  
MPI: enabled  
netcdf (default file format): enabled  
Parallel netcdf: disabled  
HDF5 C++ (legacy file format): disabled

Channelflow components  
nsolver: enabled  
Python wrapper: disabled  
GTest unit testing: enabled

– Configuring done  
– Generating done  
– Build files have been written to: /home/chihin/Repositories/channelflow/build