plot_fft.c running 
a16=
0.000000, 0.382600, 0.707100, 0.923800 
1.000000, 0.923800, 0.707100, 0.382600 
0.000000, -0.382600, -0.707100, -0.923800 
-1.000000, -0.923800, -0.707100, -0.382600 
FFT of a16, complex cxb16=
(0.000000,0.000000), (0.000000,7.999561), (0.000000,0.000000), (0.000000,-0.000207) 
(0.000000,0.000000), (0.000000,-0.000166), (0.000000,0.000000), (0.000000,-0.000401) 
(0.000000,0.000000), (0.000000,0.000402), (0.000000,0.000000), (0.000000,0.000170) 
(0.000000,0.000000), (0.000000,0.000203), (0.000000,0.000000), (0.000000,-7.999562) 
absolute value of FFT, b16= 
0.000000, 0.499973, 0.000000, 0.000013 
0.000000, 0.000010, 0.000000, 0.000025 
0.000000, 0.000025, 0.000000, 0.000011 
0.000000, 0.000013, 0.000000, 0.499973 
inverse FFT of cxb16, complex cxc16=
(0.000000,0.000000), (0.382600,-0.000000), (0.707101,0.000001), (0.923802,0.000002) 
(1.000001,0.000002), (0.923802,0.000002), (0.707102,0.000003), (0.382601,0.000002) 
(0.000000,0.000000), (-0.382600,0.000000), (-0.707101,-0.000001), (-0.923802,-0.000002) 
(-1.000001,-0.000002), (-0.923802,-0.000002), (-0.707102,-0.000003), (-0.382601,-0.000002) 
just real part of cxc16, should be a16=
0.000000, 0.382600, 0.707101, 0.923802 
1.000001, 0.923802, 0.707102, 0.382601 
0.000000, -0.382600, -0.707101, -0.923802 
-1.000001, -0.923802, -0.707102, -0.382601 
plot_fft.c finished, should have .jpg plots