```from rsf.proj import * import math Flow('mod',None, ''' sigmoid n1=200 d2=.008 n2=200 | smooth rect1=3 diff1=1 adj=y | smooth rect1=3 | scale dscale=150 ''') Plot('mod','grey title="Ideal image" ') Flow('dat','mod', ''' pad n2=1025 | cosft sign2=1 | stolt pad=513 vel=-1.5 | cosft sign2=-1 | window n2=200 ''') Plot('dat','grey title="Input data" ') Flow('t2','dat','t2stretch dens=2 | put label1="Time\^2\_" unit1="sec\^2\_" ') Plot('t2','grey title="After t\^2\_ transform" ') Result('t2','dat t2','SideBySideIso') Flow('cheb','dat','t2chebstretch dens=2 | put label1= unit1= ') Plot('cheb','grey title="Transformation to Chebyshev grid" ') Result('cheb1','dat cheb','SideBySideIso') Flow('t2-fft','t2','fft1 | fft3') Plot('t2-fft','real | grey title="Data FFT Real Part" label1=Frequency') Flow('oper','t2-fft','math output="exp(-I*x2*x2*%g/x1)" | cut n1=1' % (0.5*math.pi)) Plot('oper','real | grey title="Operator FFT Real Part" label1=Frequency') Result('t2-fft','t2-fft oper','SideBySideIso') Flow('cheb1','cheb','cosft sign1=1') Plot('cheb1','put o1=0 d1=1 | grey title="Chebyshev transform" label1="Polynom number" unit1=') Flow('cheb-fft','cheb1','cosft sign2=1') Plot('cheb-fft', ''' put o1=0 d1=1 | grey title="Chebyshev-Cosine FT" label1="Polynom number" label2=Wavenumber unit1= ''') Result('cheb1-fft','cheb1 cheb-fft','SideBySideIso') for case in ('','cheb'): for dens in (1,3): cod = '%scod%d' % (case,dens) Flow(cod,'dat','t2%sstretch dens=%d | t2%sstretch inv=y' % (case,dens,case)) Plot(cod,'grey title="Reconstructed, grid=%d" clip=0.6' % (dens*200)) dif = '%sdif%d' % (case,dens) Flow(dif,[cod,'dat'],'add scale=1,-1 \${SOURCES[1]}') Plot(dif,'grey title="Difference, grid=%d" clip=0.6' % (dens*200)) Result('fft-inv','cod1 dif1 cod3 dif3','TwoRows') Result('cheb1-inv','chebcod1 chebdif1 chebcod3 chebdif3','TwoRows') Flow('fft-mig','dat', ''' pad n2=513 | cosft sign2=1 | spray axis=2 n=1 o=0 d=1 | fourvc pad=400 pad2=512 nv=1 dv=1.5 v0=0.0001 | cosft sign3=-1 | window n3=200 ''') Plot('fft-mig','grey title="Fourier result" ') Flow('cheb-mig','dat', ''' t2chebstretch nout=513 | pad n2=513 | cosft sign1=1 sign2=1 | chebvc vel=0.75 nv=500 | cosft sign2=-1 sign1=-1 | window n2=200 | t2chebstretch inv=1 ''') Plot('cheb-mig','grey title="Chebyshev result" ') Result('mig-impl','mod dat fft-mig cheb-mig','TwoRows') End()```