Read out Fortran unformatted file in C

[msz59]

I’d say more likely values of some function of cos(theta) (x-axis) and r (y-axis). The reading should be straightforward, be it in C or Fortran but the values are somewhat strange. A typical hex value from the dump, say 8480412e00000000, represents -5.3374109887996959E-287 if big-endian or 3.8341701404960092E-315 if little-endian.