# Octave script to plot Fortran FFT output sequence from file. fid=fopen("abs.txt","r"); [v1,count]=fscanf(fid,'%f',[32, Inf]); fclose(fid); x=0:1:31; pi=3.14159; t=[0:1/64:1]; xs = sin(2*pi*5*t); subplot(2,1,1); plot(t,xs); title("Test of DIF FFT with 5-hz sine input"); xlabel("t (seconds)"); ylabel("amplitude"); subplot(2,1,2) stem(x,v1,"r"); text(15,0.45,"|X(f)| output"); ylabel ("|X(f)|"); xlabel ("frequency (hz)"); axis([0,31,0.0,0.55]); print -dpng fft_nov28.png;