itersum

这是一个射线追踪的源码

 neqs nsht nbls wtsht nitloc wtsp   zmin   eigtol  rmscut hitct
   50   0   0     0.0   3    0.50   0.00   0.020    0.002    7.

    dvpmx  dvpvsmx  idmp     vpdamp    vpvsdmp    stadamp
     0.40    0.200   0       10.000      2.000      2.000
  ires nitmax snrmct dxmax rderr ercof
  1      1  0.03000  1.25  0.10  0.01
 # its. for 1-d vel. model =   0
 rms for term. = 0.005
 fix locations for iterations =   0
 distance weighting:  50.00 200.00; residual weighting: 0.30 1.00 2.00


 unweighted rms= 0.14167; weighted rms= 0.13152 data var.(ssqrw/wnobt ie:rms**2)= 0.017296
                                                  P data var.= 0.017296
 Iteration:  0, ssqrw =      21.621  varw.(ssqrw/wndof) = 0.540510
 iteration  1 rhs solution vector:
         Velocity   : mean -0.000152339, variance    0.3655E-03, norm squared    0.3691E+00, norm    0.6076E+00
         P-Velocity : mean -0.000152339, variance    0.3655E-03, norm squared    0.3691E+00, norm    0.6076E+00

 sum of squared residuals =    25.088; total number of observations =  1250, P obs =  1250, S obs =     0
                                                     earthquake obs.=  1250, explosion obs.=     0 (wtsht= 0.00)
                    with non-zero wt:                           nwrt=  1250,          nswrt=     0
  For all 1960 P-Vel gridpts, variance=     0.00458, sd=     0.068


 unweighted rms= 0.06027; weighted rms= 0.05990 data var.(ssqrw/wnobt ie:rms**2)= 0.003588
                                                  P data var.= 0.003588


 f-test iteration  1
 new variance and ndof =   0.081555    55
 old variance and ndof =   0.540510    40
 variance ratio and critical ratio =     6.628     1.608