1SLAMCH(1)           LAPACK auxiliary routine (version 3.2)           SLAMCH(1)
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NAME

6       SLAMCH - single precision machine parameters
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SYNOPSIS

9       REAL FUNCTION SLAMCH( CMACH )
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11           CHARACTER CMACH
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PURPOSE

14       SLAMCH determines single precision machine parameters.
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ARGUMENTS

18       CMACH   (input) CHARACTER*1
19               Specifies the value to be returned by SLAMCH:
20               = 'E' or 'e',   SLAMCH := eps
21               = 'S' or 's ,   SLAMCH := sfmin
22               = 'B' or 'b',   SLAMCH := base
23               = 'P' or 'p',   SLAMCH := eps*base
24               = 'N' or 'n',   SLAMCH := t
25               = 'R' or 'r',   SLAMCH := rnd
26               = 'M' or 'm',   SLAMCH := emin
27               = 'U' or 'u',   SLAMCH := rmin
28               = 'L' or 'l',   SLAMCH := emax
29               = 'O' or 'o',   SLAMCH := rmax
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31               where
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33       eps   = relative machine precision
34             sfmin = safe minimum, such that 1/sfmin does not overflow base  =
35             base of the machine prec  = eps*base t      =  number  of  (base)
36             digits  in the mantissa rnd   = 1.0 when rounding occurs in addi‐
37             tion, 0.0 otherwise emin  =  minimum  exponent  before  (gradual)
38             underflow  rmin   =  underflow threshold - base**(emin-1) emax  =
39             largest exponent before overflow rmax  =  overflow  threshold   -
40             (base**emax)*(1-eps)
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44 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       SLAMCH(1)