functions in rays.i - p


    picture_rays(xpict, ypict, ray)  
 or picture_rays(xpict, ypict, ray, theta_up, phi_up)  

returns 2-D array of rays, one at the center of each zone (which  
represents a pixel here) of the mesh (XPICT, YPICT).  The rays are  
all parallel to the given RAY (a 3, 5, or 6 element vector).  The  
(XPICT, YPICT) coordinates are in the plane perpendicular to the rays,  
with the origin XPICT=YPICT=0 at the given RAY.  
If (THETA_UP, PHI_UP) are given, the +YPICT-axis will lie along the  
projection of the (THETA_UP, PHI_UP) direction into the (XPICT, YPICT)  
plane.  The default (THETA_UP, PHI_UP) is (pi/2, pi/2) -- the +y-axis  
-- unless (THETA, PHI) is the y-axis, in which case it is (pi/2, 0)  
-- the +x-axis.  This matches the DIRT/TDG ray coordinate convention  
in the sense that if RAY is [0,0,theta], then  
(zncen(XPICT),zncen(YPICT)) are the DIRT/TDG (x,y) coordinates for  
the rays.  
If XPICT and YPICT are imax-by-jmax, the returned array will have  
dimensions 5-by-(imax-1)-by-(jmax-1).  That is, "best" coordinates  
are returned.  The (x,y,z) of all of the returned rays will lie in  
the plane perpendicular to the ray passing through the given central  
Interpreted function, defined at i/rays.i   line 265  

SEE ALSO: form_rays,   best_rays,   dirt_rays,   internal_rays,   area  


    plray, ray  

where RAY is a vector of length 5 representing [x, y, z, theta, phi]  
-- a point (x,y,z) on the ray, and the ray direction (theta,phi)  
relative to the z-axis.  The ray hyperbola is plotted with the  
z-axis horizontal.  The portion of the ray plotted is determined  
by the plray_lims command, which must be issued prior to the first  
The 3 and 6 component ray formats are also accepted.  
Interpreted function, defined at i/rays.i   line 340  

SEE ALSO: plray_lims,   dirt_rays,   internal_rays  


    plray_lims, zmin, zmax, rmax  

sets the (z,r) coordinate limits for the plray command.  Subsequent  
rays will be clipped to the region from z=ZMIN to z=ZMAX, and from  
r=0 to r=RMAX.  
Interpreted function, defined at i/rays.i   line 475  

SEE ALSO: plray