[Discuss-gnuradio] FFT size constraints?

[John Ackermann N8UR]

By convention, FFT sizes seem to be powers of 2.  And Gnu Radio 
Companion throws an error if you try to set a size of 16384 -- but will 
accept 16383.

In some cases, I'd like to match FFT size to sample rate.  For example, 
with a 100 sample/second rate, I'd like to use a 100 bin FFT to 
(hopefully) get 1.0 frames per second.

Is using a non-power-of-2 FFT simply less efficient, or are there other 
concerns?

And is there a reason why GRC sets the limit at one less than 16384?  If 
8192 is the max because of power-of-two requirements, it would be more 
helpful to state the limitation as ">8192" rather than "<16384".

Thanks,
John