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

6       DLAISNAN - routine i not for general use
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SYNOPSIS

9       LOGICAL FUNCTION DLAISNAN(DIN1,DIN2)
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11           DOUBLE       PRECISION DIN1,DIN2
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PURPOSE

14       This  routine  is not for general use.  It exists solely to avoid over-
15       optimization in DISNAN.
16       DLAISNAN checks for NaNs by comparing its two arguments for inequality.
17       NaN  is  the  only floating-point value where NaN != NaN returns .TRUE.
18       To check for NaNs, pass the same variable as both arguments.
19       A compiler must assume that the two arguments are
20       not the same variable, and the test will not be optimized away.  Inter‐
21       procedural  or  whole-program  optimization  may delete this test.  The
22       ISNAN functions will be replaced by the correct  Fortran  03  intrinsic
23       once the intrinsic is widely available.
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ARGUMENTS

26       DIN1     (input) DOUBLE PRECISION
27                DIN2      (input)  DOUBLE PRECISION Two numbers to compare for
28                inequality.
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32 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                     DLAISNAN(1)