Numerical Definitions

Numerical Definitions — mathematical constants, and floating point decomposition

Synopsis

#include <glib.h>

#define             G_IEEE754_FLOAT_BIAS
#define             G_IEEE754_DOUBLE_BIAS
union               GFloatIEEE754;
union               GDoubleIEEE754;


#define             G_E
#define             G_LN2
#define             G_LN10
#define             G_PI
#define             G_PI_2
#define             G_PI_4
#define             G_SQRT2
#define             G_LOG_2_BASE_10

Description

GLib offers mathematical constants such as G_PI for the value of pi; many platforms have these in the C library, but some don't, the GLib versions always exist.

The GFloatIEEE754 and GDoubleIEEE754 unions are used to access the sign, mantissa and exponent of IEEE floats and doubles. These unions are defined as appropriate for a given platform. IEEE floats and doubles are supported (used for storage) by at least Intel, PPC and Sparc, for reference: http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html

Details

G_IEEE754_FLOAT_BIAS

#define             G_IEEE754_FLOAT_BIAS

See http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html


G_IEEE754_DOUBLE_BIAS

#define             G_IEEE754_DOUBLE_BIAS

See http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html


union GFloatIEEE754


The GFloatIEEE754 and GDoubleIEEE754 unions are used to access the sign, mantissa and exponent of IEEE floats and doubles. These unions are defined as appropriate for a given platform. IEEE floats and doubles are supported (used for storage) by at least Intel, PPC and Sparc, for reference: http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html


union GDoubleIEEE754


The GFloatIEEE754 and GDoubleIEEE754 unions are used to access the sign, mantissa and exponent of IEEE floats and doubles. These unions are defined as appropriate for a given platform. IEEE floats and doubles are supported (used for storage) by at least Intel, PPC and Sparc, for reference: http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html


G_E

#define             G_E

The base of natural logarithms.


G_LN2

#define             G_LN2

The natural logarithm of 2.


G_LN10

#define             G_LN10

The natural logarithm of 10.


G_PI

#define             G_PI

The value of pi (ratio of circle's circumference to its diameter).


G_PI_2

#define             G_PI_2

Pi divided by 2.


G_PI_4

#define             G_PI_4

Pi divided by 4.


G_SQRT2

#define             G_SQRT2

The square root of two.


G_LOG_2_BASE_10

#define             G_LOG_2_BASE_10

Used for fooling around with float formats, see http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html

See Also

http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html