26 lines
		
	
	
		
			951 B
		
	
	
	
		
			Groff
		
	
	
	
	
	
			
		
		
	
	
			26 lines
		
	
	
		
			951 B
		
	
	
	
		
			Groff
		
	
	
	
	
	
.TH FPCLASSIFY 3  "December 18, 2009"
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.UC 4
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.SH NAME
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fpclassify, isfinite, isinf, isnan, isnormal, signbit \- classify floating point numbers
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.SH SYNOPSIS
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.nf
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.ft B
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#include <math.h>
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int fpclassify(double \fIx\fP):
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int isfinite(double \fIx\fP);
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int isinf(double \fIx\fP);
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int isnan(double \fIx\fP);
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int isnormal(double \fIx\fP);
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int signbit(double \fIx\fP);
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.fi
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.SH DESCRIPTION
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These functions provide information about the specified floating point number 
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\fIx\fP. fpclassify returns one of the values FP_INFINITE, FP_NAN, FP_NORMAL,
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FP_SUBNORMAL and FP_ZERO depending on the type of number provided. The isinf,
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isinf, isnan and isnormal test for specific number classes, returning a 
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non-zero value is and only if the specified number belongs to the class 
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specified by the function name. The signbit function returns a non-zero value
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if and only if the sign bit is set, which for non-NaN values (including zero)
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means that the number is negative.
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