lsame.f

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*> \brief \b LSAME
*
*  =========== DOCUMENTATION ===========
*
* Online html documentation available at
*            http://www.netlib.org/lapack/explore-html/
*
*  Definition:
*  ===========
*
*       LOGICAL FUNCTION LSAME(CA,CB)
*
*       .. Scalar Arguments ..
*       CHARACTER CA,CB
*       ..
*
*
*> \par Purpose:
*  =============
*>
*> \verbatim
*>
*> LSAME returns .TRUE. if CA is the same letter as CB regardless of
*> case.
*> \endverbatim
*
*  Arguments:
*  ==========
*
*> \param[in] CA
*> \verbatim
*>          CA is CHARACTER*1
*> \endverbatim
*>
*> \param[in] CB
*> \verbatim
*>          CB is CHARACTER*1
*>          CA and CB specify the single characters to be compared.
*> \endverbatim
*
*  Authors:
*  ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \ingroup aux_blas
*
*  =====================================================================
      LOGICAL FUNCTION lsame(CA,CB)
*
*  -- Reference BLAS level1 routine --
*  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      CHARACTER ca,cb
*     ..
*
* =====================================================================
*
*     .. Intrinsic Functions ..
      INTRINSIC ichar
*     ..
*     .. Local Scalars ..
      INTEGER inta,intb,zcode
*     ..
*
*     Test if the characters are equal
*
      lsame = ca .EQ. cb
      IF (lsame) RETURN
*
*     Now test for equivalence if both characters are alphabetic.
*
      zcode = ichar('z')
*
*     Use 'Z' rather than 'A' so that ASCII can be detected on Prime
*     machines, on which ICHAR returns a value with bit 8 set.
*     ICHAR('A') on Prime machines returns 193 which is the same as
*     ICHAR('A') on an EBCDIC machine.
*
      INTA = ICHAR(CA)
      INTB = ICHAR(CB)
*
.EQ..OR..EQ.      IF (ZCODE90  ZCODE122) THEN
*
*        ASCII is assumed - ZCODE is the ASCII code of either lower or
*        upper case 'Z'.
*
.GE..AND..LE.          IF (INTA97  INTA122) INTA = INTA - 32
.GE..AND..LE.          IF (INTB97  INTB122) INTB = INTB - 32
*
.EQ..OR..EQ.      ELSE IF (ZCODE233  ZCODE169) THEN
*
*        EBCDIC is assumed - ZCODE is the EBCDIC code of either lower or
*        upper case 'Z'.
*
.GE..AND..LE..OR.          IF (INTA129  INTA137 
.GE..AND..LE..OR.     +        INTA145  INTA153 
.GE..AND..LE.     +        INTA162  INTA169) INTA = INTA + 64
.GE..AND..LE..OR.          IF (INTB129  INTB137 
.GE..AND..LE..OR.     +        INTB145  INTB153 
.GE..AND..LE.     +        INTB162  INTB169) INTB = INTB + 64
*
.EQ..OR..EQ.      ELSE IF (ZCODE218  ZCODE250) THEN
*
*        ASCII is assumed, on Prime machines - ZCODE is the ASCII code
*        plus 128 of either lower or upper case 'Z'.
*
.GE..AND..LE.          IF (INTA225  INTA250) INTA = INTA - 32
.GE..AND..LE.          IF (INTB225  INTB250) INTB = INTB - 32
      END IF
.EQ.      LSAME = INTA  INTB
*
*     RETURN
*
*     End of LSAME
*
      END