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<section id="floating-point-objects">
<span id="floatobjects"></span><h1>Floating Point Objects<a class="headerlink" href="#floating-point-objects" title="Permalink to this headline">¶</a></h1>
<span class="target" id="index-0"></span><dl class="c type">
<dt class="sig sig-object c" id="c.PyFloatObject">
<span class="k"><span class="pre">type</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloatObject</span></span></span><a class="headerlink" href="#c.PyFloatObject" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>This subtype of <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span></code></a> represents a Python floating point object.</p>
</dd></dl>
<dl class="c var">
<dt class="sig sig-object c" id="c.PyFloat_Type">
<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_Type</span></span></span><a class="headerlink" href="#c.PyFloat_Type" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>This instance of <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyTypeObject</span></code></a> represents the Python floating point
type. This is the same object as <a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a> in the Python layer.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_Check">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_Check</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">p</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_Check" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if its argument is a <a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a> or a subtype of
<a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a>. This function always succeeds.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_CheckExact">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_CheckExact</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">p</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_CheckExact" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if its argument is a <a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a>, but not a subtype of
<a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a>. This function always succeeds.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_FromString">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_FromString</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">str</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_FromString" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Create a <a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a> object based on the string value in <em>str</em>, or
<code class="docutils literal notranslate"><span class="pre">NULL</span></code> on failure.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_FromDouble">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_FromDouble</span></span></span><span class="sig-paren">(</span><span class="kt"><span class="pre">double</span></span><span class="w"> </span><span class="n"><span class="pre">v</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_FromDouble" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Create a <a class="reference internal" href="#c.PyFloatObject" title="PyFloatObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFloatObject</span></code></a> object from <em>v</em>, or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> on failure.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_AsDouble">
<span class="kt"><span class="pre">double</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_AsDouble</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">pyfloat</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_AsDouble" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return a C <span class="c-expr sig sig-inline c"><span class="kt">double</span></span> representation of the contents of <em>pyfloat</em>. If
<em>pyfloat</em> is not a Python floating point object but has a <code class="xref py py-meth docutils literal notranslate"><span class="pre">__float__()</span></code>
method, this method will first be called to convert <em>pyfloat</em> into a float.
If <code class="docutils literal notranslate"><span class="pre">__float__()</span></code> is not defined then it falls back to <code class="xref py py-meth docutils literal notranslate"><span class="pre">__index__()</span></code>.
This method returns <code class="docutils literal notranslate"><span class="pre">-1.0</span></code> upon failure, so one should call
<a class="reference internal" href="exceptions.html#c.PyErr_Occurred" title="PyErr_Occurred"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_Occurred()</span></code></a> to check for errors.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.8: </span>Use <code class="xref py py-meth docutils literal notranslate"><span class="pre">__index__()</span></code> if available.</p>
</div>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_AS_DOUBLE">
<span class="kt"><span class="pre">double</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_AS_DOUBLE</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">pyfloat</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_AS_DOUBLE" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return a C <span class="c-expr sig sig-inline c"><span class="kt">double</span></span> representation of the contents of <em>pyfloat</em>, but
without error checking.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_GetInfo">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_GetInfo</span></span></span><span class="sig-paren">(</span><span class="kt"><span class="pre">void</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_GetInfo" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return a structseq instance which contains information about the
precision, minimum and maximum values of a float. It’s a thin wrapper
around the header file <code class="file docutils literal notranslate"><span class="pre">float.h</span></code>.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_GetMax">
<span class="kt"><span class="pre">double</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_GetMax</span></span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_GetMax" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return the maximum representable finite float <em>DBL_MAX</em> as C <span class="c-expr sig sig-inline c"><span class="kt">double</span></span>.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyFloat_GetMin">
<span class="kt"><span class="pre">double</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyFloat_GetMin</span></span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyFloat_GetMin" title="Permalink to this definition">¶</a><br /></dt>
<dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return the minimum normalized positive float <em>DBL_MIN</em> as C <span class="c-expr sig sig-inline c"><span class="kt">double</span></span>.</p>
</dd></dl>
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