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slabad

 NAME
      SLABAD - take as input the values computed by SLAMCH for
      underflow and overflow, and returns the square root of each
      of these values if the log of LARGE is sufficiently large

 SYNOPSIS
      SUBROUTINE SLABAD( SMALL, LARGE )

          REAL           LARGE, SMALL

 PURPOSE
      SLABAD takes as input the values computed by SLAMCH for
      underflow and overflow, and returns the square root of each
      of these values if the log of LARGE is sufficiently large.
      This subroutine is intended to identify machines with a
      large exponent range, such as the Crays, and redefine the
      underflow and overflow limits to be the square roots of the
      values computed by SLAMCH.  This subroutine is needed
      because SLAMCH does not compensate for poor arithmetic in
      the upper half of the exponent range, as is found on a Cray.

 ARGUMENTS
      SMALL   (input/output) REAL
              On entry, the underflow threshold as computed by
              SLAMCH.  On exit, if LOG10(LARGE) is sufficiently
              large, the square root of SMALL, otherwise
              unchanged.

      LARGE   (input/output) REAL
              On entry, the overflow threshold as computed by
              SLAMCH.  On exit, if LOG10(LARGE) is sufficiently
              large, the square root of LARGE, otherwise
              unchanged.