gen/FreeBSD/isgreater.3

   1 .\" Copyright (c) 2003 David Schultz <dschultz@uclink.Berkeley.EDU>
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  27 .Dd February 12, 2003
  28 .Dt ISGREATER 3
  29 .Os
  30 .Sh NAME
  31 .Nm isgreater , isgreaterequal , isless , islessequal ,
  32 .Nm islessgreater , isunordered
  33 .Nd "compare two floating-point numbers"
  34 .Sh LIBRARY
  35 .Lb libc
  36 .Sh SYNOPSIS
  37 .In math.h
  38 .Ft int
  39 .Fn isgreater "real-floating x" "real-floating y"
  40 .Ft int
  41 .Fn isgreaterequal "real-floating x" "real-floating y"
  42 .Ft int
  43 .Fn isless "real-floating x" "real-floating y"
  44 .Ft int
  45 .Fn islessequal "real-floating x" "real-floating y"
  46 .Ft int
  47 .Fn islessgreater "real-floating x" "real-floating y"
  48 .Ft int
  49 .Fn isunordered "real-floating x" "real-floating y"
  50 .Sh DESCRIPTION
  51 Each of the macros
  52 .Fn isgreater ,
  53 .Fn isgreaterequal ,
  54 .Fn isless ,
  55 .Fn islessequal ,
  56 and
  57 .Fn islessgreater
  58 take arguments
  59 .Fa x
  60 and
  61 .Fa y
  62 and return a non-zero value if and only if its nominal
  63 relation on
  64 .Fa x
  65 and
  66 .Fa y
  67 is true.
  68 These macros always return zero if either
  69 argument is not a number (NaN), but unlike the corresponding C
  70 operators, they never raise a floating point exception.
  71 .Pp
  72 The
  73 .Fn isunordered
  74 macro takes arguments
  75 .Fa x
  76 and
  77 .Fa y
  78 and returns non-zero if and only if neither
  79 .Fa x
  80 nor
  81 .Fa y
  82 are NaNs.
  83 For any pair of floating-point values, one
  84 of the relationships (less, greater, equal, unordered) holds.
  85 .Sh SEE ALSO
  86 .Xr fpclassify 3 ,
  87 .Xr math 3 ,
  88 .Xr signbit 3
  89 .Sh STANDARDS
  90 The
  91 .Fn isgreater ,
  92 .Fn isgreaterequal ,
  93 .Fn isless ,
  94 .Fn islessequal ,
  95 .Fn islessgreater ,
  96 and
  97 .Fn isunordered
  98 macros conform to
  99 .St -isoC-99 .
 100 .Sh HISTORY
 101 The relational macros described above first appeared in
 102 .Fx 5.1 .