Synopsis
		sfunif2 < surface.rsf > model.rsf x0= z0= v00= dvdx= dvdz= n1= d1= o1=0. label1= unit1=

In each layer, velocity is a linear function of position.

Inspired by SU's unif2.

October 2013 program of the month:
http://ahay.org/blog/2013/10/03/program-of-the-month-sfunif2/

Parameters
		float d1= Sampling of the depth axis   floats dvdx= [ninf]   floats dvdz= [ninf]   string label1= depth axis label   int n1= Number of samples on the depth axis   float o1=0. Origin of the depth axis   string unit1=   floats v00= [ninf]   floats x0= [ninf]   floats z0= [ninf]

Used In
		CWP          geo2008IsotropicAngleDomainElasticRTM/marm2allA geo2008IsotropicAngleDomainElasticRTM/marm2oneA geo2009TTIModeSeparation/fold   DIRACK          examples/crestack examples/modelAndStack examples/pefInterpolation   GEO384W          hw1/wave hw5/hyper hw5/hyper2 hw5/lsmig hw6/hyper   JLU          gvdseisint/ocmodel spefdecon/wedge txyapf/french txyspfint/french   OSU          shalek/elastic2d shalek/mod2d   RSF          reprobook/exam3 reprobook/exam4 reprobook/exam5 rsf/wedge school2015/modmig scons/rsf su/rsffdmod2 su/rsflab5 su/rsfmodel su/rsfsmooth3d tutorials/scicolormaps tutorials/tuning tutorials/wedge   SEP          angle/agmig geostat/dix oc2/cup   TCCS          oc3/french oc3/frenchint ovc/psovc probdif/noisy-synthetic probdif/synthetic probdif/toy simistack/flat4 sparse/sparse-experim-shaping   ZJU          diffrlrra/synth