MAKEVEL - MAKE a VELocity function v(x,y,z)

makevel > outfile nx= nz= [optional parameters]

Required Parameters:
nx= number of x samples (3rd dimension)
nz= number of z samples (1st dimension)

Optional Parameters:
ny=1 number of y samples (2nd dimension)
dx=1.0 x sampling interval
fx=0.0 first x sample
dy=1.0 y sampling interval
fy=0.0 first y sample
dz=1.0 z sampling interval
fz=0.0 first z sample
v000=2.0 velocity at (x=0,y=0,z=0)
dvdx=0.0 velocity gradient with respect to x
dvdy=0.0 velocity gradient with respect to y
dvdz=0.0 velocity gradient with respect to z
vlens=0.0 velocity perturbation in parabolic lens
tlens=0.0 thickness of parabolic lens
dlens=0.0 diameter of parabolic lens
xlens= x coordinate of center of parabolic lens
ylens= y coordinate of center of parabolic lens
zlens= z coordinate of center of parabolic lens
vran=0.0 standard deviation of random perturbation
vzfile= file containing v(z) profile
vzran=0.0 standard deviation of random perturbation to v(z)
vzc=0.0 v(z) chirp amplitude
z1c=fz z at which to begin chirp
z2c=fz+(nz-1)*dz z at which to end chirp
l1c=dz wavelength at beginning of chirp
l2c=dz wavelength at end of chirp
exc=1.0 exponent of chirp