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Mise à jour du répertoire tools et de la bibliothèque lapack.

    1: *> \brief \b DLAMCH
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at 
    6: *            http://www.netlib.org/lapack/explore-html/ 
    7: *
    8: *  Definition:
    9: *  ===========
   10: *
   11: *      DOUBLE PRECISION FUNCTION DLAMCH( CMACH )
   12: *  
   13: *
   14: *> \par Purpose:
   15: *  =============
   16: *>
   17: *> \verbatim
   18: *>
   19: *> DLAMCH determines double precision machine parameters.
   20: *> \endverbatim
   21: *
   22: *  Arguments:
   23: *  ==========
   24: *
   25: *> \param[in] CMACH
   26: *> \verbatim
   27: *>          Specifies the value to be returned by DLAMCH:
   28: *>          = 'E' or 'e',   DLAMCH := eps
   29: *>          = 'S' or 's ,   DLAMCH := sfmin
   30: *>          = 'B' or 'b',   DLAMCH := base
   31: *>          = 'P' or 'p',   DLAMCH := eps*base
   32: *>          = 'N' or 'n',   DLAMCH := t
   33: *>          = 'R' or 'r',   DLAMCH := rnd
   34: *>          = 'M' or 'm',   DLAMCH := emin
   35: *>          = 'U' or 'u',   DLAMCH := rmin
   36: *>          = 'L' or 'l',   DLAMCH := emax
   37: *>          = 'O' or 'o',   DLAMCH := rmax
   38: *>          where
   39: *>          eps   = relative machine precision
   40: *>          sfmin = safe minimum, such that 1/sfmin does not overflow
   41: *>          base  = base of the machine
   42: *>          prec  = eps*base
   43: *>          t     = number of (base) digits in the mantissa
   44: *>          rnd   = 1.0 when rounding occurs in addition, 0.0 otherwise
   45: *>          emin  = minimum exponent before (gradual) underflow
   46: *>          rmin  = underflow threshold - base**(emin-1)
   47: *>          emax  = largest exponent before overflow
   48: *>          rmax  = overflow threshold  - (base**emax)*(1-eps)
   49: *> \endverbatim
   50: *
   51: *  Authors:
   52: *  ========
   53: *
   54: *> \author Univ. of Tennessee 
   55: *> \author Univ. of California Berkeley 
   56: *> \author Univ. of Colorado Denver 
   57: *> \author NAG Ltd. 
   58: *
   59: *> \date November 2011
   60: *
   61: *> \ingroup auxOTHERauxiliary
   62: *
   63: *  =====================================================================
   64:       DOUBLE PRECISION FUNCTION DLAMCH( CMACH )
   65: *
   66: *  -- LAPACK auxiliary routine (version 3.4.0) --
   67: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
   68: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   69: *     November 2011
   70: *
   71: *     .. Scalar Arguments ..
   72:       CHARACTER          CMACH
   73: *     ..
   74: *
   75: * =====================================================================
   76: *
   77: *     .. Parameters ..
   78:       DOUBLE PRECISION   ONE, ZERO
   79:       PARAMETER          ( ONE = 1.0D+0, ZERO = 0.0D+0 )
   80: *     ..
   81: *     .. Local Scalars ..
   82:       DOUBLE PRECISION   RND, EPS, SFMIN, SMALL, RMACH
   83: *     ..
   84: *     .. External Functions ..
   85:       LOGICAL            LSAME
   86:       EXTERNAL           LSAME
   87: *     ..
   88: *     .. Intrinsic Functions ..
   89:       INTRINSIC          DIGITS, EPSILON, HUGE, MAXEXPONENT,
   90:      $                   MINEXPONENT, RADIX, TINY
   91: *     ..
   92: *     .. Executable Statements ..
   93: *
   94: *
   95: *     Assume rounding, not chopping. Always.
   96: *
   97:       RND = ONE
   98: *
   99:       IF( ONE.EQ.RND ) THEN
  100:          EPS = EPSILON(ZERO) * 0.5
  101:       ELSE
  102:          EPS = EPSILON(ZERO)
  103:       END IF
  104: *
  105:       IF( LSAME( CMACH, 'E' ) ) THEN
  106:          RMACH = EPS
  107:       ELSE IF( LSAME( CMACH, 'S' ) ) THEN
  108:          SFMIN = TINY(ZERO)
  109:          SMALL = ONE / HUGE(ZERO)
  110:          IF( SMALL.GE.SFMIN ) THEN
  111: *
  112: *           Use SMALL plus a bit, to avoid the possibility of rounding
  113: *           causing overflow when computing  1/sfmin.
  114: *
  115:             SFMIN = SMALL*( ONE+EPS )
  116:          END IF
  117:          RMACH = SFMIN
  118:       ELSE IF( LSAME( CMACH, 'B' ) ) THEN
  119:          RMACH = RADIX(ZERO)
  120:       ELSE IF( LSAME( CMACH, 'P' ) ) THEN
  121:          RMACH = EPS * RADIX(ZERO)
  122:       ELSE IF( LSAME( CMACH, 'N' ) ) THEN
  123:          RMACH = DIGITS(ZERO)
  124:       ELSE IF( LSAME( CMACH, 'R' ) ) THEN
  125:          RMACH = RND
  126:       ELSE IF( LSAME( CMACH, 'M' ) ) THEN
  127:          RMACH = MINEXPONENT(ZERO)
  128:       ELSE IF( LSAME( CMACH, 'U' ) ) THEN
  129:          RMACH = tiny(zero)
  130:       ELSE IF( LSAME( CMACH, 'L' ) ) THEN
  131:          RMACH = MAXEXPONENT(ZERO)
  132:       ELSE IF( LSAME( CMACH, 'O' ) ) THEN
  133:          RMACH = HUGE(ZERO)
  134:       ELSE
  135:          RMACH = ZERO
  136:       END IF
  137: *
  138:       DLAMCH = RMACH
  139:       RETURN
  140: *
  141: *     End of DLAMCH
  142: *
  143:       END
  144: ************************************************************************
  145: *> \brief \b DLAMC3
  146: *> \details
  147: *> \b Purpose:
  148: *> \verbatim
  149: *> DLAMC3  is intended to force  A  and  B  to be stored prior to doing
  150: *> the addition of  A  and  B ,  for use in situations where optimizers
  151: *> might hold one of these in a register.
  152: *> \endverbatim
  153: *> \author LAPACK is a software package provided by Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..
  154: *> \date November 2011
  155: *> \ingroup auxOTHERauxiliary
  156: *>
  157: *> \param[in] A
  158: *> \verbatim
  159: *>          A is a DOUBLE PRECISION
  160: *> \endverbatim
  161: *>
  162: *> \param[in] B
  163: *> \verbatim
  164: *>          B is a DOUBLE PRECISION
  165: *>          The values A and B.
  166: *> \endverbatim
  167: *>
  168:       DOUBLE PRECISION FUNCTION DLAMC3( A, B )
  169: *
  170: *  -- LAPACK auxiliary routine (version 3.4.0) --
  171: *     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
  172: *     November 2010
  173: *
  174: *     .. Scalar Arguments ..
  175:       DOUBLE PRECISION   A, B
  176: *     ..
  177: * =====================================================================
  178: *
  179: *     .. Executable Statements ..
  180: *
  181:       DLAMC3 = A + B
  182: *
  183:       RETURN
  184: *
  185: *     End of DLAMC3
  186: *
  187:       END
  188: *
  189: ************************************************************************