I'm looking to compute an IDFT but my input is very sparse:
Example:
- IDFT length: 7,408,800 (complex floats)
- Sparsity: 96.61% to 99.99%
I found this Sparse FFT website but it looks like the library deals with sparse inputs to standard DFT - not IDFT - also it doesn't look like it is not for consumer use.
Are there any techniques I can employ to improve performance for sparse IDFT - before even changing my DFT library? And now, are there any available libraries that give performance improvements for spare IDFT?