```from rsf.proj import * Flow('spike',None, ''' spike n1=256 n2=256 d1=0.004 d2=0.008 nsp=3 k1=100,150,200 k2=100,150,200 | bandpass flo=10 fhi=50 ''') ffts = [] for pad in (256,512): spike = 'spike%d' % pad Flow(spike,'spike','pad n2=%d' % pad) for dv in (1,-1): fft = 'fft%d-%d' % (dv,pad) ffts.append(fft) Flow(fft,spike, ''' cosft sign2=1 | spray axis=2 n=1 o=0 d=0.008 | fourvc pad=%d pad2=%d nv=1 dv=%d v0=%g | cosft sign3=-1 | window n3=256 ''' % (pad,(pad,2*pad)[pad==512],2*dv,(2.0001,0.0001)[dv==1])) Plot(fft,'grey title="t^2-FFT impulse response, dv=%d km/s"' % dv) Result('fft-imp',ffts,'TwoRows') ffts = [] for pad in (256,512): spike = 'spike%d' % pad for dv in (1,-1): fft = 'foc%d-%d' % (dv,pad) ffts.append(fft) Flow(fft,spike, ''' diffoc pad=%d pad2=%d v=%g v0=%g | window n2=256 ''' % (pad,(pad,2*pad)[pad==512],(0.0001,2.0001)[dv==1],(2.0001,0.0001)[dv==1])) Plot(fft,'grey title="t^2-FFT impulse response, dv=%d km/s"' % dv) Result('foc-imp',ffts,'TwoRows') for adj in (0,1): fd = 'fd%d' % adj Flow(fd,'spike512', 'velcon vel=1 v0=0 nv=3000 inv=%d adj=%d | window n2=256' % (adj,1-adj)) Plot(fd, 'grey title="Finite-diff impulse response, dv=%d km/s" ' % (1-2*adj)) Result('fd-imp','fd0 fd1','SideBySideIso') Flow('chebft','spike','t2chebstretch nout=257 | pad n2=257 | cosft sign1=1 sign2=1') chebs = [] for pad in (256,512): for dv in (1,-1): cheb = 'cheb%d-%d' % (dv,pad) chebs.append(cheb) Flow(cheb,'spike', ''' t2chebstretch nout=257 | pad n2=%d | cosft sign1=1 sign2=1 | chebvc vel=%g nv=3000 | cosft sign2=-1 sign1=-1 | window n2=256 | t2chebstretch inv=1 ''' % (pad+1,dv)) Plot(cheb,'grey title="Chebyshev impulse response, dv=%g km/s" ' % dv) Result('cheb-impl',chebs,'TwoRows') End()```