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- PATH
- LD_RUN_PATH
- PKG_CONFIG_PATH
- LIBRARY_PATH
The modules do not have any effect during runtime.
Precision
On Unix, You may link to -lfftw3f (single) or -lfftw3l (long-double) instead of or in addition to -lfftw3 (double).
You can see all provided versions directly after you loaded an a FFTW module with: ls ${LIBRARY_PATH%%:*}
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