[unix-history] / usr / src / lib / libc / gen / isinf.3

.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)isinf.3	5.3 (Berkeley) %G%
.\"
.Dd 
.Dt ISINF 3
.Os
.Sh NAME
.Nm isinf ,
.Nm isnan
.Nd test for infinity or not-a-number (\*(Na)
.Sh SYNOPSIS
.Ft int 
.Fn isinf double
.Ft int 
.Fn isnan double
.Sh DESCRIPTION
The
.Fn isninf
function
returns 1 if the number is
.Dq \\*(If ,
otherwise 0.
.Pp
The
.Fn isnan
function
returns 1 if the number is
.Dq \\*(Na ,
otherwise 0.
.Sh SEE ALSO
.Xr math 3
.Rs
.%T "IEEE Standard for Binary Floating-Point Arithmetic"
.%Q ANSI
.%R Std 754-1985
.Re
.Sh BUGS
Neither the
.Tn VAX
nor the Tahoe floating point have distinguished values
for either infinity or not-a-number.
These routines always return 0 on those architectures.
Commit	Line	Data
2fa7067f	1	.\" Copyright (c) 1991 The Regents of the University of California.
26c1d2b2 KB	2	.\" All rights reserved.
	3	.\"
	4	.\" %sccs.include.redist.man%
	5	.\"
2fa7067f	6	.\" @(#)isinf.3 5.3 (Berkeley) %G%
26c1d2b2	7	.\"
d5001484 CL	8	.Dd
	9	.Dt ISINF 3
	10	.Os
	11	.Sh NAME
	12	.Nm isinf ,
	13	.Nm isnan
	14	.Nd test for infinity or not-a-number (\*(Na)
	15	.Sh SYNOPSIS
	16	.Ft int
	17	.Fn isinf double
	18	.Ft int
	19	.Fn isnan double
	20	.Sh DESCRIPTION
	21	The
	22	.Fn isninf
	23	function
	24	returns 1 if the number is
	25	.Dq \\*(If ,
	26	otherwise 0.
	27	.Pp
	28	The
	29	.Fn isnan
	30	function
	31	returns 1 if the number is
	32	.Dq \\*(Na ,
	33	otherwise 0.
	34	.Sh SEE ALSO
	35	.Xr math 3
	36	.Rs
	37	.%T "IEEE Standard for Binary Floating-Point Arithmetic"
	38	.%Q ANSI
	39	.%R Std 754-1985
	40	.Re
	41	.Sh BUGS
	42	Neither the
	43	.Tn VAX
	44	nor the Tahoe floating point have distinguished values
26c1d2b2 KB	45	for either infinity or not-a-number.
26c1d2b2 KB	46	These routines always return 0 on those architectures.