functions in drat.i - s

             set_tolerances()  
          or old_tols= set_tolerances([tol1, tol2, lost_tol])  
 
     returns the current tolerances for the ray tracking.  Initially,  
     these are [1.e-3, 1.e-6, 0.0].  In the second form, sets new  
     tolerances.  If any of TOL1, TOL2, or LOST_TOL is zero, that  
     tolerance is restored to its default value.  If TOL1 is less  
     than zero, the root polishing operation which requires TOL1  
     and TOL2 is not done at all.  
builtin function, documented at i0/drat.i   line 1274  

             snap(f, rays)  
          or snap(f, rays, slimits)  
 
     returns the time-integrated specific intensity for the rad-hydro  
     problem dumped in file F, on the specified RAYS, with the  
     specified limits SLIMITS on the transport integrals.  
     The first dimension of RAYS may be length 3, 5, or 6 to represent  
     the ray(s) in TDG/DIRT coordinates (x,y,theta), "best" coordinates  
     (x,y,z,theta,phi), or internal coordinates (cos,sin,y,z,x,r),  
     respectively.  The remaining dimensions of RAYS, if any, will be  
     called "nrays" below.  
     The SLIMITS parameter, if present, is the value of the s-coordinate  
     -- position along the ray -- at which to start and stop the  
     integration of the transport equation.  SLIMITS may be nil, a 1-D  
     array of length 2, or a 2-by-nrays array.  Each component of SLIMITS  
     is [s_start, s_stop]; if s_stop line 193  

             snap_worker(transp, selfem, time)  
 
     The snap function actually works by replacing the drat_compress  
     with snap_worker.  See the source for snap in drat.i for details.  
interpreted function, defined at i0/drat.i   line 272  

             streak(f, rays)  
          or streak(f, rays, slimits)  
 
     returns the transparency and self-emission as functions of time for  
     the rad-hydro problem dumped in file F, on the specified RAYS, with  
     the specified limits SLIMITS on the transport integrals.  
     The first dimension of RAYS may be length 3, 5, or 6 to represent  
     the ray(s) in TDG/DIRT coordinates (x,y,theta), "best" coordinates  
     (x,y,z,theta,phi), or internal coordinates (cos,sin,y,z,x,r),  
     respectively.  The remaining dimensions of RAYS, if any, will be  
     called "nrays" below.  
     The SLIMITS parameter, if present, is the value of the s-coordinate  
     -- position along the ray -- at which to start and stop the  
     integration of the transport equation.  SLIMITS may be nil, a 1-D  
     array of length 2, or a 2-by-nrays array.  Each component of SLIMITS  
     is [s_start, s_stop]; if s_stop line 38  

             streak_save, outname, f, rays  
          or streak_save, outname, f, rays, slimits  
          or streak_save, outfile, f, rays, slimits  
 
     is the same as the streak function, except that the results of  
     the transport calculation are placed into a PDB file called  
     OUTNAME, instead of being accumulated in memory.  All of the  
     options for the streak function are available, except for  
     drat_compress (which is set to streak_saver).  
     If the first argument is OUTFILE, a file variable instead of a  
     file name, then that file is used for output.  You can create  
     OUTFILE and add static variables to it with save (but do NOT call  
     add_record) which streak_save otherwise wouldn't know about.  
     The output file has history records at the same times as the  
     input file.  Each record contains "time" (a double scalar),  
     and the two arrays "transp", the transparency (between 0 and 1),  
     and "selfem", the self emission (which has the same units as  
     ekap in the file F).  The dimensions of transp and selfem  
     are ngroup-by-2-by-nrays (where nrays represents zero or more  
     dimensions, copied from the RAYS input array).  The RAYS and  
     SLIMITS inputs are placed into the output file as non-record  
     variables, and any variables in the drat_static option are  
     copied form F to the output file.  The gb and gav variables  
     are copied from F into the output file as well.  If the drat_glist  
     option is present, that is stored in the output file also.  
   OPTIONS: all options available for streak except drat_compress,  
            drat_gb, drat_gav, drat_static  
interpreted function, defined at i0/drat.i   line 295  

             streak_saver(transp, selfem, time)  
 
     The streak_save function actually works by replacing the drat_compress  
     with streak_saver.  See the source for streak_saver in drat.i for  
     details.  
interpreted function, defined at i0/drat.i   line 366  

             streak_times(f)  
 
     returns the times from file F whic lie between the optional  
     drat_start and drat_stop.  
interpreted function, defined at i0/drat.i   line 897