1*4882a593Smuzhiyunconfig BR2_PACKAGE_FFTW 2*4882a593Smuzhiyun bool "fftw" 3*4882a593Smuzhiyun select BR2_PACKAGE_FFTW_DOUBLE if !BR2_PACKAGE_FFTW_SINGLE \ 4*4882a593Smuzhiyun && !BR2_PACKAGE_FFTW_LONG_DOUBLE && !BR2_PACKAGE_FFTW_QUAD 5*4882a593Smuzhiyun help 6*4882a593Smuzhiyun Library for computing Fast Fourier Transforms. 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun This library computes Fast Fourier Transforms (FFT) in one 9*4882a593Smuzhiyun or more dimensions. It is extremely fast. This package 10*4882a593Smuzhiyun contains the shared library version of the fftw libraries in 11*4882a593Smuzhiyun double precision. 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun http://www.fftw.org 14*4882a593Smuzhiyun 15*4882a593Smuzhiyunif BR2_PACKAGE_FFTW 16*4882a593Smuzhiyun 17*4882a593Smuzhiyunsource "package/fftw/fftw-single/Config.in" 18*4882a593Smuzhiyunsource "package/fftw/fftw-double/Config.in" 19*4882a593Smuzhiyunsource "package/fftw/fftw-long-double/Config.in" 20*4882a593Smuzhiyunsource "package/fftw/fftw-quad/Config.in" 21*4882a593Smuzhiyun 22*4882a593Smuzhiyunconfig BR2_PACKAGE_FFTW_FAST 23*4882a593Smuzhiyun bool "optimise for speed over accuracy" 24*4882a593Smuzhiyun help 25*4882a593Smuzhiyun Optimise for fast math functions, at the expense of accuracy. 26*4882a593Smuzhiyun 27*4882a593Smuzhiyun Say 'y' if you need speed and can live with inaccuracies in 28*4882a593Smuzhiyun the results. Say 'n' (the default) if accuracy is of utmost 29*4882a593Smuzhiyun importance. 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun This basically uses gcc's -Ofast optimisation level, which in 32*4882a593Smuzhiyun turn is basically using gcc's -ffast-math. See the gcc manual 33*4882a593Smuzhiyun for what this means. 34*4882a593Smuzhiyun 35*4882a593Smuzhiyunendif 36