Specialized Update Keyword Routines

1

These update routines modify the value, and optionally the comment field, of the keyword if it already exists, otherwise the new keyword is appended to the header. A separate routine is provided for each keyword datatype. A null pointer may be entered for the comment parameter which will leave the comment field unchanged or blank.  

  int fits_update_key_str / ffukys
      (fitsfile *fptr, char *keyname, char *value, char *comment,
       > int *status)

  int fits_update_key_[log, lng] / ffuky[lj]
      (fitsfile *fptr, char *keyname, DTYPE numval, char *comment,
       > int *status)

  int fits_update_key_[flt, dbl, fixflt, fixdbl] / ffuky[edfg]
      (fitsfile *fptr, char *keyname, DTYPE numval, int decimals,
       char *comment, > int *status)

  int fits_update_key_[cmp, dblcmp, fixcmp, fixdblcmp] / ffuk[yc,ym,fc,fm]
      (fitsfile *fptr, char *keyname, DTYPE *numval, int decimals,
       char *comment, > int *status)