/sys$common/syshlp/helplib.hlb FORTRAN, Error Messages, Run Time Errors, General, LOGZERNEG  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  NUMBER:  83

  ERROR CODE:  F, C

  MESSAGE TEXT:  logarithm of zero or negative value

  EXPLANATION:  An attempt was made to take the logarithm of zero or
  a negative number.  The result returned was the reserved operand,
  -0.