| <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> |
| <html> |
| <head> |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> |
| <title>Numerical Definitions</title> |
| <meta name="generator" content="DocBook XSL Stylesheets V1.75.2"> |
| <link rel="home" href="index.html" title="GLib Reference Manual"> |
| <link rel="up" href="glib-fundamentals.html" title="GLib Fundamentals"> |
| <link rel="prev" href="glib-Byte-Order-Macros.html" title="Byte Order Macros"> |
| <link rel="next" href="glib-Miscellaneous-Macros.html" title="Miscellaneous Macros"> |
| <meta name="generator" content="GTK-Doc V1.14 (XML mode)"> |
| <link rel="stylesheet" href="style.css" type="text/css"> |
| </head> |
| <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> |
| <table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2"> |
| <tr valign="middle"> |
| <td><a accesskey="p" href="glib-Byte-Order-Macros.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td> |
| <td><a accesskey="u" href="glib-fundamentals.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td> |
| <td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td> |
| <th width="100%" align="center">GLib Reference Manual</th> |
| <td><a accesskey="n" href="glib-Miscellaneous-Macros.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td> |
| </tr> |
| <tr><td colspan="5" class="shortcuts"> |
| <a href="#glib-Numerical-Definitions.synopsis" class="shortcut">Top</a> |
| | |
| <a href="#glib-Numerical-Definitions.description" class="shortcut">Description</a> |
| </td></tr> |
| </table> |
| <div class="refentry" title="Numerical Definitions"> |
| <a name="glib-Numerical-Definitions"></a><div class="titlepage"></div> |
| <div class="refnamediv"><table width="100%"><tr> |
| <td valign="top"> |
| <h2><span class="refentrytitle"><a name="glib-Numerical-Definitions.top_of_page"></a>Numerical Definitions</span></h2> |
| <p>Numerical Definitions — mathematical constants, and floating point decomposition</p> |
| </td> |
| <td valign="top" align="right"></td> |
| </tr></table></div> |
| <div class="refsynopsisdiv" title="Synopsis"> |
| <a name="glib-Numerical-Definitions.synopsis"></a><h2>Synopsis</h2> |
| <pre class="synopsis"> |
| #include <glib.h> |
| |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-IEEE754-FLOAT-BIAS:CAPS" title="G_IEEE754_FLOAT_BIAS">G_IEEE754_FLOAT_BIAS</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-IEEE754-DOUBLE-BIAS:CAPS" title="G_IEEE754_DOUBLE_BIAS">G_IEEE754_DOUBLE_BIAS</a> |
| union <a class="link" href="glib-Numerical-Definitions.html#GFloatIEEE754" title="union GFloatIEEE754">GFloatIEEE754</a>; |
| union <a class="link" href="glib-Numerical-Definitions.html#GDoubleIEEE754" title="union GDoubleIEEE754">GDoubleIEEE754</a>; |
| |
| |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-E:CAPS" title="G_E">G_E</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-LN2:CAPS" title="G_LN2">G_LN2</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-LN10:CAPS" title="G_LN10">G_LN10</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-PI:CAPS" title="G_PI">G_PI</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-PI-2:CAPS" title="G_PI_2">G_PI_2</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-PI-4:CAPS" title="G_PI_4">G_PI_4</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-SQRT2:CAPS" title="G_SQRT2">G_SQRT2</a> |
| #define <a class="link" href="glib-Numerical-Definitions.html#G-LOG-2-BASE-10:CAPS" title="G_LOG_2_BASE_10">G_LOG_2_BASE_10</a> |
| </pre> |
| </div> |
| <div class="refsect1" title="Description"> |
| <a name="glib-Numerical-Definitions.description"></a><h2>Description</h2> |
| <p> |
| GLib offers mathematical constants such as <a class="link" href="glib-Numerical-Definitions.html#G-PI:CAPS" title="G_PI"><span class="type">G_PI</span></a> for the value of pi; |
| many platforms have these in the C library, but some don't, the GLib |
| versions always exist. |
| </p> |
| <p> |
| The <a class="link" href="glib-Numerical-Definitions.html#GFloatIEEE754" title="union GFloatIEEE754"><span class="type">GFloatIEEE754</span></a> and <a class="link" href="glib-Numerical-Definitions.html#GDoubleIEEE754" title="union GDoubleIEEE754"><span class="type">GDoubleIEEE754</span></a> 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: <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| <div class="refsect1" title="Details"> |
| <a name="glib-Numerical-Definitions.details"></a><h2>Details</h2> |
| <div class="refsect2" title="G_IEEE754_FLOAT_BIAS"> |
| <a name="G-IEEE754-FLOAT-BIAS:CAPS"></a><h3>G_IEEE754_FLOAT_BIAS</h3> |
| <pre class="programlisting">#define G_IEEE754_FLOAT_BIAS (127) |
| </pre> |
| <p> |
| See <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_IEEE754_DOUBLE_BIAS"> |
| <a name="G-IEEE754-DOUBLE-BIAS:CAPS"></a><h3>G_IEEE754_DOUBLE_BIAS</h3> |
| <pre class="programlisting">#define G_IEEE754_DOUBLE_BIAS (1023) |
| </pre> |
| <p> |
| See <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="union GFloatIEEE754"> |
| <a name="GFloatIEEE754"></a><h3>union GFloatIEEE754</h3> |
| <pre class="programlisting"></pre> |
| <p> |
| The <a class="link" href="glib-Numerical-Definitions.html#GFloatIEEE754" title="union GFloatIEEE754"><span class="type">GFloatIEEE754</span></a> and <a class="link" href="glib-Numerical-Definitions.html#GDoubleIEEE754" title="union GDoubleIEEE754"><span class="type">GDoubleIEEE754</span></a> 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: |
| <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="union GDoubleIEEE754"> |
| <a name="GDoubleIEEE754"></a><h3>union GDoubleIEEE754</h3> |
| <pre class="programlisting"></pre> |
| <p> |
| The <a class="link" href="glib-Numerical-Definitions.html#GFloatIEEE754" title="union GFloatIEEE754"><span class="type">GFloatIEEE754</span></a> and <a class="link" href="glib-Numerical-Definitions.html#GDoubleIEEE754" title="union GDoubleIEEE754"><span class="type">GDoubleIEEE754</span></a> 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: |
| <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_E"> |
| <a name="G-E:CAPS"></a><h3>G_E</h3> |
| <pre class="programlisting">#define G_E 2.7182818284590452353602874713526624977572470937000 |
| </pre> |
| <p> |
| The base of natural logarithms. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_LN2"> |
| <a name="G-LN2:CAPS"></a><h3>G_LN2</h3> |
| <pre class="programlisting">#define G_LN2 0.69314718055994530941723212145817656807550013436026 |
| </pre> |
| <p> |
| The natural logarithm of 2. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_LN10"> |
| <a name="G-LN10:CAPS"></a><h3>G_LN10</h3> |
| <pre class="programlisting">#define G_LN10 2.3025850929940456840179914546843642076011014886288 |
| </pre> |
| <p> |
| The natural logarithm of 10. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_PI"> |
| <a name="G-PI:CAPS"></a><h3>G_PI</h3> |
| <pre class="programlisting">#define G_PI 3.1415926535897932384626433832795028841971693993751 |
| </pre> |
| <p> |
| The value of pi (ratio of circle's circumference to its diameter). |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_PI_2"> |
| <a name="G-PI-2:CAPS"></a><h3>G_PI_2</h3> |
| <pre class="programlisting">#define G_PI_2 1.5707963267948966192313216916397514420985846996876 |
| </pre> |
| <p> |
| Pi divided by 2. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_PI_4"> |
| <a name="G-PI-4:CAPS"></a><h3>G_PI_4</h3> |
| <pre class="programlisting">#define G_PI_4 0.78539816339744830961566084581987572104929234984378 |
| </pre> |
| <p> |
| Pi divided by 4. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_SQRT2"> |
| <a name="G-SQRT2:CAPS"></a><h3>G_SQRT2</h3> |
| <pre class="programlisting">#define G_SQRT2 1.4142135623730950488016887242096980785696718753769 |
| </pre> |
| <p> |
| The square root of two. |
| </p> |
| </div> |
| <hr> |
| <div class="refsect2" title="G_LOG_2_BASE_10"> |
| <a name="G-LOG-2-BASE-10:CAPS"></a><h3>G_LOG_2_BASE_10</h3> |
| <pre class="programlisting">#define G_LOG_2_BASE_10 (0.30102999566398119521) |
| </pre> |
| <p> |
| Used for fooling around with float formats, see |
| <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| </div> |
| <div class="refsect1" title="See Also"> |
| <a name="glib-Numerical-Definitions.see-also"></a><h2>See Also</h2> |
| <p> |
| <a class="ulink" href="http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html" target="_top">http://cch.loria.fr/documentation/IEEE754/numerical_comp_guide/ncg_math.doc.html</a> |
| </p> |
| </div> |
| </div> |
| <div class="footer"> |
| <hr> |
| Generated by GTK-Doc V1.14</div> |
| </body> |
| </html> |