For file input, the points are specified as free-format sequence of R, Z pairs in a file prepared by the user. This file can have an arbitrary name. There is no header. Output appears in two files. File BTOR.DAT is the same, except it gives Btor.
Output is written in three files.
The larger file BPOL.DAT contains R points, Z points, plus Bpol and Btor at those points, for both the boundary surface and the specified surface. A graphic metafile 55MFIT.POP is also written, and it can be plotted in any of the usual ways. There are two prompts. One can also choose to plot only the boundary surface. The second prompt asks for the actual numerical flux value in the chosen units.