User’s own ray data file.
There is an option for the user to specify the initial conditions of the rays in a user-supplied file that is read by the program.
Intended for large sets of individual rays, but can also be used for other types (where it can be useful for batch running).
After the program has read the name of the user-supplied file it switches to reading from that file. Therefore the file must contain exactly the same type of data that would be produced by the databuilder. For example, a set of rays must start with at least the first 3 letters of 'set of single rays' and must finish with at least the first 3 letters of 'last of this set of rays' These lines must be followed by those that would be produced by the databuilder in a normal cpo data input file. You must retain the standard format when letters are involved but otherwise any number of spaces (>0) can be used between numbers. Comments at the ends of lines are not read.
The databuilder cannot be used to edit the user-supplied file.
The footnotes are not read from either file and so are lost.
The user can also manually edit the input data file.
But manual editing is certainly not recommended -it is a relic from the time when the databuilder was not available All users are strongly encouraged to use the databuilder, which always gives the correct formats and which has many options for which the formats are not described or easily deduced.
The program requires a first line that starts with ‘y’ if ray tracing is required, or ‘n’ if it is not (in which case the program will go straight to the display mode, for contour plots etc.).
The program requires a first line that starts with the 8 characters:
-for example a suitable line (as used above) is:
'start of ray information’
If ray tracing is not wanted, then put the line:
'no ray information'
in which case the program will go straight to the display mode, for contour plots etc.
If the program cannot find either type of line then it will go to the display mode.
Return to general note on ray tracing.