<!-- ##### SECTION Title ##### -->Numerical Definitions<!-- ##### SECTION Short_Description ##### -->mathematical constants, and floating point decomposition<!-- ##### SECTION Long_Description ##### --><para>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 GLibversions always exist.</para><para>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: <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### SECTION See_Also ##### --><para><ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### SECTION Stability_Level ##### --><!-- ##### MACRO G_IEEE754_FLOAT_BIAS ##### --><para>See <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### MACRO G_IEEE754_DOUBLE_BIAS ##### --><para>See <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### UNION GFloatIEEE754 ##### --><para>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: <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### UNION GDoubleIEEE754 ##### --><para>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: <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para><!-- ##### MACRO G_E ##### --><para>The base of natural logarithms.</para><!-- ##### MACRO G_LN2 ##### --><para>The natural logarithm of 2.</para><!-- ##### MACRO G_LN10 ##### --><para>The natural logarithm of 10.</para><!-- ##### MACRO G_PI ##### --><para>The value of pi (ratio of circle's circumference to its diameter).</para><!-- ##### MACRO G_PI_2 ##### --><para>Pi divided by 2.</para><!-- ##### MACRO G_PI_4 ##### --><para>Pi divided by 4.</para><!-- ##### MACRO G_SQRT2 ##### --><para>The square root of two.</para><!-- ##### MACRO G_LOG_2_BASE_10 ##### --><para>Used for fooling around with float formats, see <ulink url="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</ulink></para>