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ISINF(3)		 BSD Library Functions Manual		      ISINF(3)

NAME
     isinf, isnan, isnanf -- test for infinity or not-a-number

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     int
     isinf(double);

     int
     isnan(double);

     int
     isnanf(float);

DESCRIPTION
     The isinf() function returns 1 if the number is "infinity", otherwise 0.

     The isnan() and isnanf() functions	return 1 if the	double or float	(re-
     spectively) is "not-a-number", otherwise 0.

SEE ALSO
     math(3)

     IEEE Standard for Binary Floating-Point Arithmetic, Std 754-1985, ANSI.

BUGS
     Neither the VAX nor the Tahoe floating point have distinguished values
     for either	infinity or not-a-number.  These routines always return	0 on
     those architectures.

BSD			       January 29, 1994				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | BUGS

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