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<section id="index-0">
<span id="memoryview-objects"></span><span id="id1"></span><h1>MemoryView objects<a class="headerlink" href="#index-0" title="Link to this heading"></a></h1>
<p>A <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate"><span class="pre">memoryview</span></code></a> object exposes the C level <a class="reference internal" href="buffer.html#bufferobjects"><span class="std std-ref">buffer interface</span></a> as a Python object which can then be passed around like
any other object.</p>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_FromObject">
<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">PyMemoryView_FromObject</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">obj</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromObject" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">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 memoryview object from an object that provides the buffer interface.
If <em>obj</em> supports writable buffer exports, the memoryview object will be
read/write, otherwise it may be either read-only or read/write at the
discretion of the exporter.</p>
</dd></dl>
<dl class="c macro">
<dt class="sig sig-object c" id="c.PyBUF_READ">
<span class="sig-name descname"><span class="n"><span class="pre">PyBUF_READ</span></span></span><a class="headerlink" href="#c.PyBUF_READ" title="Link to this definition"></a><br /></dt>
<dd><p>Flag to request a readonly buffer.</p>
</dd></dl>
<dl class="c macro">
<dt class="sig sig-object c" id="c.PyBUF_WRITE">
<span class="sig-name descname"><span class="n"><span class="pre">PyBUF_WRITE</span></span></span><a class="headerlink" href="#c.PyBUF_WRITE" title="Link to this definition"></a><br /></dt>
<dd><p>Flag to request a writable buffer.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_FromMemory">
<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">PyMemoryView_FromMemory</span></span></span><span class="sig-paren">(</span><span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">mem</span></span>, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><span class="n"><span class="pre">Py_ssize_t</span></span></a><span class="w"> </span><span class="n"><span class="pre">size</span></span>, <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="n"><span class="pre">flags</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromMemory" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">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> since version 3.7.</em><p>Create a memoryview object using <em>mem</em> as the underlying buffer.
<em>flags</em> can be one of <a class="reference internal" href="#c.PyBUF_READ" title="PyBUF_READ"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_READ</span></code></a> or <a class="reference internal" href="#c.PyBUF_WRITE" title="PyBUF_WRITE"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_WRITE</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified added">Added in version 3.3.</span></p>
</div>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_FromBuffer">
<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">PyMemoryView_FromBuffer</span></span></span><span class="sig-paren">(</span><span class="k"><span class="pre">const</span></span><span class="w"> </span><a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><span class="n"><span class="pre">Py_buffer</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">view</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromBuffer" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">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> since version 3.11.</em><p>Create a memoryview object wrapping the given buffer structure <em>view</em>.
For simple byte buffers, <a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> is the preferred
function.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_GetContiguous">
<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">PyMemoryView_GetContiguous</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">obj</span></span>, <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="n"><span class="pre">buffertype</span></span>, <span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="n"><span class="pre">order</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GetContiguous" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">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 memoryview object to a <a class="reference internal" href="../glossary.html#term-contiguous"><span class="xref std std-term">contiguous</span></a> chunk of memory (in either
C or Fortran <em>order</em>) from an object that defines the buffer
interface. If memory is contiguous, the memoryview object points to the
original memory. Otherwise, a copy is made and the memoryview points to a
new bytes object.</p>
<p><em>buffertype</em> can be one of <a class="reference internal" href="#c.PyBUF_READ" title="PyBUF_READ"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_READ</span></code></a> or <a class="reference internal" href="#c.PyBUF_WRITE" title="PyBUF_WRITE"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_WRITE</span></code></a>.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_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">PyMemoryView_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">obj</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_Check" title="Link to this definition"></a><br /></dt>
<dd><p>Return true if the object <em>obj</em> is a memoryview object. It is not
currently allowed to create subclasses of <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate"><span class="pre">memoryview</span></code></a>. This
function always succeeds.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_GET_BUFFER">
<a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><span class="n"><span class="pre">Py_buffer</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">PyMemoryView_GET_BUFFER</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">mview</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BUFFER" title="Link to this definition"></a><br /></dt>
<dd><p>Return a pointer to the memoryviews private copy of the exporters buffer.
<em>mview</em> <strong>must</strong> be a memoryview instance; this macro doesnt check its type,
you must do it yourself or you will risk crashes.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyMemoryView_GET_BASE">
<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">PyMemoryView_GET_BASE</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">mview</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BASE" title="Link to this definition"></a><br /></dt>
<dd><p>Return either a pointer to the exporting object that the memoryview is based
on or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> if the memoryview has been created by one of the functions
<a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> or <a class="reference internal" href="#c.PyMemoryView_FromBuffer" title="PyMemoryView_FromBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromBuffer()</span></code></a>.
<em>mview</em> <strong>must</strong> be a memoryview instance.</p>
</dd></dl>
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