.TH "slamchf77.f" 3 "Wed Oct 15 2014" "Version 3.4.2" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
slamchf77.f \- 
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "real function \fBslamch\fP (CMACH)"
.br
.RI "\fI\fBSLAMCHF77\fP deprecated \fP"
.ti -1c
.RI "subroutine \fBslamc1\fP (BETA, T, RND, IEEE1)"
.br
.RI "\fI\fBSLAMC1\fP \fP"
.ti -1c
.RI "subroutine \fBslamc2\fP (BETA, T, RND, EPS, EMIN, RMIN, EMAX, RMAX)"
.br
.RI "\fI\fBSLAMC2\fP \fP"
.ti -1c
.RI "real function \fBslamc3\fP (A, B)"
.br
.RI "\fI\fBSLAMC3\fP \fP"
.ti -1c
.RI "subroutine \fBslamc4\fP (EMIN, START, BASE)"
.br
.RI "\fI\fBSLAMC4\fP \fP"
.ti -1c
.RI "subroutine \fBslamc5\fP (BETA, P, EMIN, IEEE, EMAX, RMAX)"
.br
.RI "\fI\fBSLAMC5\fP \fP"
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine slamc1 (integerBETA, integerT, logicalRND, logicalIEEE1)"

.PP
\fBSLAMC1\fP \fBPurpose:\fP 
.PP
.nf
 SLAMC1 determines the machine parameters given by BETA, T, RND, and
 IEEE1.
.fi
.PP
.PP
\fBParameters:\fP
.RS 4
\fIBETA\fP 
.PP
.nf
          The base of the machine.
.fi
.PP
.br
\fIT\fP 
.PP
.nf
          The number of ( BETA ) digits in the mantissa.
.fi
.PP
.br
\fIRND\fP 
.PP
.nf
          Specifies whether proper rounding  ( RND = .TRUE. )  or
          chopping  ( RND = .FALSE. )  occurs in addition. This may not
          be a reliable guide to the way in which the machine performs
          its arithmetic.
.fi
.PP
.br
\fIIEEE1\fP 
.PP
.nf
          Specifies whether rounding appears to be done in the IEEE
          'round to nearest' style.
.fi
.PP
 
.RE
.PP
\fBAuthor:\fP
.RS 4
LAPACK is a software package provided by Univ\&. of Tennessee, Univ\&. of California Berkeley, Univ\&. of Colorado Denver and NAG Ltd\&.\&. 
.RE
.PP
\fBDate:\fP
.RS 4
April 2012
.RE
.PP
\fBFurther\fP \fBDetails\fP 
.PP
.nf
  The routine is based on the routine  ENVRON  by Malcolm and
  incorporates suggestions by Gentleman and Marovich. See

     Malcolm M. A. (1972) Algorithms to reveal properties of
        floating-point arithmetic. Comms. of the ACM, 15, 949-951.

     Gentleman W. M. and Marovich S. B. (1974) More on algorithms
        that reveal properties of floating point arithmetic units.
        Comms. of the ACM, 17, 276-277.
.fi
.PP
 
.PP
Definition at line 210 of file slamchf77\&.f\&.
.SS "subroutine slamc2 (integerBETA, integerT, logicalRND, realEPS, integerEMIN, realRMIN, integerEMAX, realRMAX)"

.PP
\fBSLAMC2\fP \fBPurpose:\fP 
.PP
.nf
 SLAMC2 determines the machine parameters specified in its argument
 list.
.fi
.PP
 
.PP
\fBAuthor:\fP
.RS 4
LAPACK is a software package provided by Univ\&. of Tennessee, Univ\&. of California Berkeley, Univ\&. of Colorado Denver and NAG Ltd\&.\&. 
.RE
.PP
\fBDate:\fP
.RS 4
April 2012
.RE
.PP
\fBParameters:\fP
.RS 4
\fIBETA\fP 
.PP
.nf
          The base of the machine.
.fi
.PP
.br
\fIT\fP 
.PP
.nf
          The number of ( BETA ) digits in the mantissa.
.fi
.PP
.br
\fIRND\fP 
.PP
.nf
          Specifies whether proper rounding  ( RND = .TRUE. )  or
          chopping  ( RND = .FALSE. )  occurs in addition. This may not
          be a reliable guide to the way in which the machine performs
          its arithmetic.
.fi
.PP
.br
\fIEPS\fP 
.PP
.nf
          The smallest positive number such that
             fl( 1.0 - EPS ) .LT. 1.0,
          where fl denotes the computed value.
.fi
.PP
.br
\fIEMIN\fP 
.PP
.nf
          The minimum exponent before (gradual) underflow occurs.
.fi
.PP
.br
\fIRMIN\fP 
.PP
.nf
          The smallest normalized number for the machine, given by
          BASE**( EMIN - 1 ), where  BASE  is the floating point value
          of BETA.
.fi
.PP
.br
\fIEMAX\fP 
.PP
.nf
          The maximum exponent before overflow occurs.
.fi
.PP
.br
\fIRMAX\fP 
.PP
.nf
          The largest positive number for the machine, given by
          BASE**EMAX * ( 1 - EPS ), where  BASE  is the floating point
          value of BETA.
.fi
.PP
.RE
.PP
\fBFurther\fP \fBDetails\fP 
.PP
.nf
  The computation of  EPS  is based on a routine PARANOIA by
  W. Kahan of the University of California at Berkeley.
.fi
.PP
 
.PP
Definition at line 423 of file slamchf77\&.f\&.
.SS "real function slamc3 (realA, realB)"

.PP
\fBSLAMC3\fP \fBPurpose:\fP 
.PP
.nf
 SLAMC3  is intended to force  A  and  B  to be stored prior to doing
 the addition of  A  and  B ,  for use in situations where optimizers
 might hold one of these in a register.
.fi
.PP
.PP
\fBParameters:\fP
.RS 4
\fIA\fP 
.br
\fIB\fP 
.PP
.nf
          The values A and B.
.fi
.PP
 
.RE
.PP

.PP
Definition at line 646 of file slamchf77\&.f\&.
.SS "subroutine slamc4 (integerEMIN, realSTART, integerBASE)"

.PP
\fBSLAMC4\fP \fBPurpose:\fP 
.PP
.nf
 SLAMC4 is a service routine for SLAMC2.
.fi
.PP
.PP
\fBParameters:\fP
.RS 4
\fIEMIN\fP 
.PP
.nf
          The minimum exponent before (gradual) underflow, computed by
          setting A = START and dividing by BASE until the previous A
          can not be recovered.
.fi
.PP
.br
\fISTART\fP 
.PP
.nf
          The starting point for determining EMIN.
.fi
.PP
.br
\fIBASE\fP 
.PP
.nf
          The base of the machine.
.fi
.PP
 
.RE
.PP

.PP
Definition at line 693 of file slamchf77\&.f\&.
.SS "subroutine slamc5 (integerBETA, integerP, integerEMIN, logicalIEEE, integerEMAX, realRMAX)"

.PP
\fBSLAMC5\fP \fBPurpose:\fP 
.PP
.nf
 SLAMC5 attempts to compute RMAX, the largest machine floating-point
 number, without overflow.  It assumes that EMAX + abs(EMIN) sum
 approximately to a power of 2.  It will fail on machines where this
 assumption does not hold, for example, the Cyber 205 (EMIN = -28625,
 EMAX = 28718).  It will also fail if the value supplied for EMIN is
 too large (i.e. too close to zero), probably with overflow.
.fi
.PP
.PP
\fBParameters:\fP
.RS 4
\fIBETA\fP 
.PP
.nf
          The base of floating-point arithmetic.
.fi
.PP
.br
\fIP\fP 
.PP
.nf
          The number of base BETA digits in the mantissa of a
          floating-point value.
.fi
.PP
.br
\fIEMIN\fP 
.PP
.nf
          The minimum exponent before (gradual) underflow.
.fi
.PP
.br
\fIIEEE\fP 
.PP
.nf
          A logical flag specifying whether or not the arithmetic
          system is thought to comply with the IEEE standard.
.fi
.PP
.br
\fIEMAX\fP 
.PP
.nf
          The largest exponent before overflow
.fi
.PP
.br
\fIRMAX\fP 
.PP
.nf
          The largest machine floating-point number.
.fi
.PP
 
.RE
.PP

.PP
Definition at line 801 of file slamchf77\&.f\&.
.SS "real function slamch (characterCMACH)"

.PP
\fBSLAMCHF77\fP deprecated 
.PP
\fBPurpose: \fP
.RS 4

.PP
.nf
 SLAMCH determines single precision machine parameters.
.fi
.PP
 
.RE
.PP
\fBParameters:\fP
.RS 4
\fICMACH\fP 
.PP
.nf
          Specifies the value to be returned by SLAMCH:
          = 'E' or 'e',   SLAMCH := eps
          = 'S' or 's ,   SLAMCH := sfmin
          = 'B' or 'b',   SLAMCH := base
          = 'P' or 'p',   SLAMCH := eps*base
          = 'N' or 'n',   SLAMCH := t
          = 'R' or 'r',   SLAMCH := rnd
          = 'M' or 'm',   SLAMCH := emin
          = 'U' or 'u',   SLAMCH := rmin
          = 'L' or 'l',   SLAMCH := emax
          = 'O' or 'o',   SLAMCH := rmax
          where
          eps   = relative machine precision
          sfmin = safe minimum, such that 1/sfmin does not overflow
          base  = base of the machine
          prec  = eps*base
          t     = number of (base) digits in the mantissa
          rnd   = 1.0 when rounding occurs in addition, 0.0 otherwise
          emin  = minimum exponent before (gradual) underflow
          rmin  = underflow threshold - base**(emin-1)
          emax  = largest exponent before overflow
          rmax  = overflow threshold  - (base**emax)*(1-eps)
.fi
.PP
 
.RE
.PP
\fBAuthor:\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBDate:\fP
.RS 4
April 2012 
.RE
.PP

.PP
Definition at line 68 of file slamchf77\&.f\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.