fft_time.c  P3 450MHz MS 
N=16 FFT time=6e-006 
     inv time=9.5e-006 
    both time=1.5275e-005 

N=32 FFT time=1.655e-005 
     inv time=2.1e-005 
    both time=3.555e-005 

N=64 FFT time=3.41e-005 
     inv time=4.81e-005 
    both time=7.71e-005 

N=128 FFT time=8.4e-005 
     inv time=0.0001022 
    both time=0.0001822 

N=256 FFT time=0.0001724 
     inv time=0.0002204 
    both time=0.0003844 

N=512 FFT time=0.00042 
     inv time=0.000482 
    both time=0.00088 

N=1024 FFT time=0.000884 
     inv time=0.00108 
    both time=0.001884 

N=2048 FFT time=0.0022 
     inv time=0.002355 
    both time=0.004455 

N=4096 FFT time=0.00451 
     inv time=0.00631 
    both time=0.01071