./outbgrid.h 
      1 numprocs
   -1 n_step
  0.0 t
 1.0  2.5 0  360. -84.9 84.9 plot_range
 -1.00000E+00 -1.00000E+00 -1.00000E+00  0.0319 5.625 5.625  102960  plot_dx, dxmin, ncell
      4 nplotvar
      1 neqpar
6.96e8
B_r B_lon B_lat B R_S
R R R nT nT nT nT
       T save_binary