NFFT3 is a C library for computing nonequispaced fast Fourier transforms (NFFT) and generalisations: to arbitrary knots in time and frequency (NNFFT), to the sphere S^2 (NFSFT), to the hyperbolic cross (NSFFT), to real-valued data (NFCT, NFST) and to the rotation group (NFSOFT), together with iterative inverse solvers.

WWW: https://nfft.org/
