Diameters computed with the following routines exclude super giants
and binaries! If you want to bypass the latter restriction, set the
BFLAG field to '.' (it is set to 'B' for binaries). The routine computing
the diameter from (B-V) also excludes bright giants and stars later
diameter_ri Compute diameter from color index and -magnitude.
diameter_bv Compute diameter from color index and -magnitude.