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-  <div class="section" id="cf-auxiliarycoordinate-t">
-<h1>cf.AuxiliaryCoordinate.T<a class="headerlink" href="#cf-auxiliarycoordinate-t" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.T">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">T</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.T" title="Permalink to this definition">¶</a></dt>
-<dd><p>True if and only if the data are coordinates for a CF ‘T’ axis.</p>
-<p>CF ‘T’ axis coordinates are defined by having units of reference time.</p>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.ctype.html#cf.AuxiliaryCoordinate.ctype" title="cf.AuxiliaryCoordinate.ctype"><code class="xref py py-obj docutils literal notranslate"><span class="pre">ctype</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.X.html#cf.AuxiliaryCoordinate.X" title="cf.AuxiliaryCoordinate.X"><code class="xref py py-obj docutils literal notranslate"><span class="pre">X</span></code></a>, <a class="reference internal" href="../generated/cf.Coordinate.Y.html#cf.Coordinate.Y" title="cf.Coordinate.Y"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Y</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.Z.html#cf.AuxiliaryCoordinate.Z" title="cf.AuxiliaryCoordinate.Z"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Z</span></code></a></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span>
-<span class="go">&lt;CF Units: seconds since 1992-10-8&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">T</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-</dd></dl>
-
-</div>
-
-
-          </div>
-          
-        </div>
-      </div>
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diff --git a/docs/method/cf.AuxiliaryCoordinate.X.html b/docs/method/cf.AuxiliaryCoordinate.X.html
deleted file mode 100644
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-  <div class="section" id="cf-auxiliarycoordinate-x">
-<h1>cf.AuxiliaryCoordinate.X<a class="headerlink" href="#cf-auxiliarycoordinate-x" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.X">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">X</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.X" title="Permalink to this definition">¶</a></dt>
-<dd><p>True if and only if the data are coordinates for a CF ‘X’ axis.</p>
-<p>CF ‘X’ axis coordinates are defined by having one or more of the
-following:</p>
-<blockquote>
-<div><ul class="simple">
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.axis.html#cf.AuxiliaryCoordinate.axis" title="cf.AuxiliaryCoordinate.axis"><code class="xref py py-obj docutils literal notranslate"><span class="pre">axis</span></code></a> property has the value <code class="docutils literal notranslate"><span class="pre">'X'</span></code></li>
-<li>Units of longitude</li>
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.standard_name.html#cf.AuxiliaryCoordinate.standard_name" title="cf.AuxiliaryCoordinate.standard_name"><code class="xref py py-obj docutils literal notranslate"><span class="pre">standard_name</span></code></a> property is one of <code class="docutils literal notranslate"><span class="pre">'longitude'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'projection_x_coordinate'</span></code> or <code class="docutils literal notranslate"><span class="pre">'grid_longitude'</span></code></li>
-</ul>
-</div></blockquote>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.ctype.html#cf.AuxiliaryCoordinate.ctype" title="cf.AuxiliaryCoordinate.ctype"><code class="xref py py-obj docutils literal notranslate"><span class="pre">ctype</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.T.html#cf.AuxiliaryCoordinate.T" title="cf.AuxiliaryCoordinate.T"><code class="xref py py-obj docutils literal notranslate"><span class="pre">T</span></code></a>, <a class="reference internal" href="../generated/cf.Coordinate.Y.html#cf.Coordinate.Y" title="cf.Coordinate.Y"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Y</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.Z.html#cf.AuxiliaryCoordinate.Z" title="cf.AuxiliaryCoordinate.Z"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Z</span></code></a></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span>
-<span class="go">&lt;CF Units: degreeE&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">X</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">standard_name</span>
-<span class="go">&#39;longitude&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">X</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">axis</span> <span class="o">==</span> <span class="s1">&#39;X&#39;</span> <span class="ow">and</span> <span class="n">c</span><span class="o">.</span><span class="n">X</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-</dd></dl>
-
-</div>
-
-
-          </div>
-          
-        </div>
-      </div>
-    <div class="clearer"></div>
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-      
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-      <a href="../_sources/method/cf.AuxiliaryCoordinate.X.rst.txt"
-          rel="nofollow">Page source</a>
-    </div>
-
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\ No newline at end of file
diff --git a/docs/method/cf.AuxiliaryCoordinate.Y.html b/docs/method/cf.AuxiliaryCoordinate.Y.html
deleted file mode 100644
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--- a/docs/method/cf.AuxiliaryCoordinate.Y.html
+++ /dev/null
@@ -1,138 +0,0 @@
-
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
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-  <div class="section" id="cf-auxiliarycoordinate-y">
-<h1>cf.AuxiliaryCoordinate.Y<a class="headerlink" href="#cf-auxiliarycoordinate-y" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.Y">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">Y</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.Y" title="Permalink to this definition">¶</a></dt>
-<dd><p>True if and only if the data are coordinates for a CF ‘Y’ axis.</p>
-<p>CF ‘Y’ axis coordinates are defined by having one or more of the
-following:</p>
-<blockquote>
-<div><ul class="simple">
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.axis.html#cf.AuxiliaryCoordinate.axis" title="cf.AuxiliaryCoordinate.axis"><code class="xref py py-obj docutils literal notranslate"><span class="pre">axis</span></code></a> property has the value <code class="docutils literal notranslate"><span class="pre">'Y'</span></code></li>
-<li>Units of latitude</li>
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.standard_name.html#cf.AuxiliaryCoordinate.standard_name" title="cf.AuxiliaryCoordinate.standard_name"><code class="xref py py-obj docutils literal notranslate"><span class="pre">standard_name</span></code></a> property is one of <code class="docutils literal notranslate"><span class="pre">'latitude'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'projection_y_coordinate'</span></code> or <code class="docutils literal notranslate"><span class="pre">'grid_latitude'</span></code></li>
-</ul>
-</div></blockquote>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.ctype.html#cf.AuxiliaryCoordinate.ctype" title="cf.AuxiliaryCoordinate.ctype"><code class="xref py py-obj docutils literal notranslate"><span class="pre">ctype</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.T.html#cf.AuxiliaryCoordinate.T" title="cf.AuxiliaryCoordinate.T"><code class="xref py py-obj docutils literal notranslate"><span class="pre">T</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.X.html#cf.AuxiliaryCoordinate.X" title="cf.AuxiliaryCoordinate.X"><code class="xref py py-obj docutils literal notranslate"><span class="pre">X</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.Z.html#cf.AuxiliaryCoordinate.Z" title="cf.AuxiliaryCoordinate.Z"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Z</span></code></a></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span>
-<span class="go">&lt;CF Units: degree_north&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Y</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">standard_name</span> <span class="o">==</span> <span class="s1">&#39;latitude&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Y</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-</dd></dl>
-
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-  <div class="section" id="cf-auxiliarycoordinate-z">
-<h1>cf.AuxiliaryCoordinate.Z<a class="headerlink" href="#cf-auxiliarycoordinate-z" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.Z">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">Z</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.Z" title="Permalink to this definition">¶</a></dt>
-<dd><p>True if and only if the data are coordinates for a CF ‘Z’ axis.</p>
-<p>CF ‘Z’ axis coordinates are defined by having one or more of the
-following:</p>
-<blockquote>
-<div><ul class="simple">
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.axis.html#cf.AuxiliaryCoordinate.axis" title="cf.AuxiliaryCoordinate.axis"><code class="xref py py-obj docutils literal notranslate"><span class="pre">axis</span></code></a> property has the value <code class="docutils literal notranslate"><span class="pre">'Z'</span></code></li>
-<li>Units of pressure, level, layer or sigma_level</li>
-<li>The <a class="reference internal" href="cf.AuxiliaryCoordinate.positive.html#cf.AuxiliaryCoordinate.positive" title="cf.AuxiliaryCoordinate.positive"><code class="xref py py-obj docutils literal notranslate"><span class="pre">positive</span></code></a> property has the value <code class="docutils literal notranslate"><span class="pre">'up'</span></code> or <code class="docutils literal notranslate"><span class="pre">'down'</span></code>
-(case insensitive)</li>
-<li>The <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.standard_name.html#cf.AuxiliaryCoordinate.standard_name" title="cf.AuxiliaryCoordinate.standard_name"><code class="xref py py-obj docutils literal notranslate"><span class="pre">standard_name</span></code></a> property is one of
-<code class="docutils literal notranslate"><span class="pre">'atmosphere_ln_pressure_coordinate'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'atmosphere_sigma_coordinate'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'atmosphere_hybrid_sigma_pressure_coordinate'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'atmosphere_hybrid_height_coordinate'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'atmosphere_sleve_coordinate</span></code>’, <code class="docutils literal notranslate"><span class="pre">'ocean_sigma_coordinate'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'ocean_s_coordinate'</span></code>, <code class="docutils literal notranslate"><span class="pre">'ocean_s_coordinate_g1'</span></code>,
-<code class="docutils literal notranslate"><span class="pre">'ocean_s_coordinate_g2'</span></code>, <code class="docutils literal notranslate"><span class="pre">'ocean_sigma_z_coordinate'</span></code> or
-<code class="docutils literal notranslate"><span class="pre">'ocean_double_sigma_coordinate'</span></code></li>
-</ul>
-</div></blockquote>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.ctype.html#cf.AuxiliaryCoordinate.ctype" title="cf.AuxiliaryCoordinate.ctype"><code class="xref py py-obj docutils literal notranslate"><span class="pre">ctype</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.T.html#cf.AuxiliaryCoordinate.T" title="cf.AuxiliaryCoordinate.T"><code class="xref py py-obj docutils literal notranslate"><span class="pre">T</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.X.html#cf.AuxiliaryCoordinate.X" title="cf.AuxiliaryCoordinate.X"><code class="xref py py-obj docutils literal notranslate"><span class="pre">X</span></code></a>, <a class="reference internal" href="../generated/cf.Coordinate.Y.html#cf.Coordinate.Y" title="cf.Coordinate.Y"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Y</span></code></a></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span>
-<span class="go">&lt;CF Units: Pa&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Z</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span><span class="o">.</span><span class="n">equivalent</span><span class="p">(</span><span class="n">cf</span><span class="o">.</span><span class="n">Units</span><span class="p">(</span><span class="s1">&#39;K&#39;</span><span class="p">))</span> <span class="ow">and</span> <span class="n">c</span><span class="o">.</span><span class="n">positive</span> <span class="o">==</span> <span class="s1">&#39;up&#39;</span>
-<span class="go">True</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Z</span>
-<span class="go">True </span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">axis</span> <span class="o">==</span> <span class="s1">&#39;Z&#39;</span> <span class="ow">and</span> <span class="n">c</span><span class="o">.</span><span class="n">Z</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Units</span>
-<span class="go">&lt;CF Units: sigma_level&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Z</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">standard_name</span>
-<span class="go">&#39;ocean_sigma_coordinate&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">Z</span>
-<span class="go">True</span>
-</pre></div>
-</div>
-</dd></dl>
-
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-
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-  <div class="section" id="cf-auxiliarycoordinate-bounds">
-<h1>cf.AuxiliaryCoordinate.bounds<a class="headerlink" href="#cf-auxiliarycoordinate-bounds" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.bounds">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">bounds</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.bounds" title="Permalink to this definition">¶</a></dt>
-<dd><p>Return the bounds.</p>
-<p><code class="docutils literal notranslate"><span class="pre">f.bounds</span></code> is equivalent to <code class="docutils literal notranslate"><span class="pre">f.get_bounds()</span></code></p>
-<div class="versionadded">
-<p><span class="versionmodified">New in version 1.7.0.</span></p>
-</div>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.data.html#cf.AuxiliaryCoordinate.data" title="cf.AuxiliaryCoordinate.data"><code class="xref py py-obj docutils literal notranslate"><span class="pre">data</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.del_bounds.html#cf.AuxiliaryCoordinate.del_bounds" title="cf.AuxiliaryCoordinate.del_bounds"><code class="xref py py-obj docutils literal notranslate"><span class="pre">del_bounds</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.get_bounds.html#cf.AuxiliaryCoordinate.get_bounds" title="cf.AuxiliaryCoordinate.get_bounds"><code class="xref py py-obj docutils literal notranslate"><span class="pre">get_bounds</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.has_bounds.html#cf.AuxiliaryCoordinate.has_bounds" title="cf.AuxiliaryCoordinate.has_bounds"><code class="xref py py-obj docutils literal notranslate"><span class="pre">has_bounds</span></code></a>,
-<a class="reference internal" href="cf.AuxiliaryCoordinate.set_bounds.html#cf.AuxiliaryCoordinate.set_bounds" title="cf.AuxiliaryCoordinate.set_bounds"><code class="xref py py-obj docutils literal notranslate"><span class="pre">set_bounds</span></code></a></p>
-</div>
-<table class="docutils field-list" frame="void" rules="none">
-<col class="field-name" />
-<col class="field-body" />
-<tbody valign="top">
-<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body"><dl class="first last docutils">
-<dt><a class="reference internal" href="../classes/cf.Bounds.html#cf.Bounds" title="cf.Bounds"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Bounds</span></code></a></dt>
-<dd><p class="first last">The bounds.</p>
-</dd>
-</dl>
-</td>
-</tr>
-</tbody>
-</table>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">numpy</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span> <span class="o">=</span> <span class="n">cfdm</span><span class="o">.</span><span class="n">Bounds</span><span class="p">(</span><span class="n">data</span><span class="o">=</span><span class="n">cfdm</span><span class="o">.</span><span class="n">Data</span><span class="p">(</span><span class="n">numpy</span><span class="o">.</span><span class="n">arange</span><span class="p">(</span><span class="mi">10</span><span class="p">)</span><span class="o">.</span><span class="n">reshape</span><span class="p">(</span><span class="mi">5</span><span class="p">,</span> <span class="mi">2</span><span class="p">)))</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">set_bounds</span><span class="p">(</span><span class="n">b</span><span class="p">)</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">has_bounds</span><span class="p">()</span>
-<span class="go">True</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span> <span class="o">=</span> <span class="n">c</span><span class="o">.</span><span class="n">bounds</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span>
-<span class="go">&lt;Bounds: (5, 2) &gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span><span class="o">.</span><span class="n">data</span>
-<span class="go">&lt;Data(5, 2): [[0, ..., 9]]&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span><span class="o">.</span><span class="n">data</span><span class="o">.</span><span class="n">shape</span>
-<span class="go">(5, 2)</span>
-</pre></div>
-</div>
-</dd></dl>
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diff --git a/docs/method/cf.AuxiliaryCoordinate.cellsize.html b/docs/method/cf.AuxiliaryCoordinate.cellsize.html
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-  <div class="section" id="cf-auxiliarycoordinate-cellsize">
-<h1>cf.AuxiliaryCoordinate.cellsize<a class="headerlink" href="#cf-auxiliarycoordinate-cellsize" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.cellsize">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">cellsize</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.cellsize" title="Permalink to this definition">¶</a></dt>
-<dd><p>The cell sizes.</p>
-<p>If there are no cell bounds then the cell sizes are all zero.</p>
-<div class="versionadded">
-<p><span class="versionmodified">New in version 2.0.</span></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="nb">print</span><span class="p">(</span><span class="n">c</span><span class="o">.</span><span class="n">bounds</span><span class="o">.</span><span class="n">array</span><span class="p">)</span>
-<span class="go">[[-90. -87.]</span>
-<span class="go"> [-87. -80.]</span>
-<span class="go"> [-80. -67.]]</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">cellsize</span>
-<span class="go">&lt;CF Data(3,): [3.0, 7.0, 13.0] degrees_north&gt;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="nb">print</span><span class="p">(</span><span class="n">d</span><span class="o">.</span><span class="n">cellsize</span><span class="o">.</span><span class="n">array</span><span class="p">)</span>
-<span class="go">[  3.   7.  13.]</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">b</span> <span class="o">=</span> <span class="n">c</span><span class="o">.</span><span class="n">del_bounds</span><span class="p">()</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">cellsize</span>
-<span class="go">&lt;CF Data(3,): [0, 0, 0] degrees_north&gt;</span>
-</pre></div>
-</div>
-</dd></dl>
-
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-
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deleted file mode 100644
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-  <div class="section" id="cf-auxiliarycoordinate-ctype">
-<h1>cf.AuxiliaryCoordinate.ctype<a class="headerlink" href="#cf-auxiliarycoordinate-ctype" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.ctype">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">ctype</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.ctype" title="Permalink to this definition">¶</a></dt>
-<dd><p>The CF coordinate type.</p>
-<p>One of <code class="docutils literal notranslate"><span class="pre">'T'</span></code>, <code class="docutils literal notranslate"><span class="pre">'X'</span></code>, <code class="docutils literal notranslate"><span class="pre">'Y'</span></code> or <code class="docutils literal notranslate"><span class="pre">'Z'</span></code> if the coordinate
-construct is for the respective CF axis type, otherwise <a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.7)"><code class="xref py py-obj docutils literal notranslate"><span class="pre">None</span></code></a>.</p>
-<div class="admonition seealso">
-<p class="first admonition-title">See also</p>
-<p class="last"><a class="reference internal" href="cf.AuxiliaryCoordinate.T.html#cf.AuxiliaryCoordinate.T" title="cf.AuxiliaryCoordinate.T"><code class="xref py py-obj docutils literal notranslate"><span class="pre">T</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.X.html#cf.AuxiliaryCoordinate.X" title="cf.AuxiliaryCoordinate.X"><code class="xref py py-obj docutils literal notranslate"><span class="pre">X</span></code></a>, <a class="reference internal" href="../generated/cf.Coordinate.Y.html#cf.Coordinate.Y" title="cf.Coordinate.Y"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Y</span></code></a>, <a class="reference internal" href="cf.AuxiliaryCoordinate.Z.html#cf.AuxiliaryCoordinate.Z" title="cf.AuxiliaryCoordinate.Z"><code class="xref py py-obj docutils literal notranslate"><span class="pre">Z</span></code></a></p>
-</div>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">X</span>
-<span class="go">True</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">ctype</span>
-<span class="go">&#39;X&#39;</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">T</span>
-<span class="go">True</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">ctype</span>
-<span class="go">&#39;T&#39;</span>
-</pre></div>
-</div>
-</dd></dl>
-
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-
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deleted file mode 100644
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-<h1>cf.AuxiliaryCoordinate.history<a class="headerlink" href="#cf-auxiliarycoordinate-history" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.history">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">history</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.history" title="Permalink to this definition">¶</a></dt>
-<dd><p>The history CF property.</p>
-<p>A list of the applications that have modified the original
-data. See <a class="reference external" href="http://cfconventions.org/latest.html">http://cfconventions.org/latest.html</a> for details.</p>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">history</span> <span class="o">=</span> <span class="s1">&#39;created on 2012/10/01&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">history</span>
-<span class="go">&#39;created on 2012/10/01&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="k">del</span> <span class="n">f</span><span class="o">.</span><span class="n">history</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">set_property</span><span class="p">(</span><span class="s1">&#39;history&#39;</span><span class="p">,</span> <span class="s1">&#39;created on 2012/10/01&#39;</span><span class="p">)</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">has_property</span><span class="p">(</span><span class="s1">&#39;history&#39;</span><span class="p">)</span>
-<span class="go">True</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">get_property</span><span class="p">(</span><span class="s1">&#39;history&#39;</span><span class="p">)</span>
-<span class="go">&#39;created on 2012/10/01&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">del_property</span><span class="p">(</span><span class="s1">&#39;history&#39;</span><span class="p">)</span>
-</pre></div>
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-  <div class="section" id="cf-auxiliarycoordinate-positive">
-<h1>cf.AuxiliaryCoordinate.positive<a class="headerlink" href="#cf-auxiliarycoordinate-positive" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.positive">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">positive</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.positive" title="Permalink to this definition">¶</a></dt>
-<dd><p>The positive CF property.</p>
-<p>The direction of positive (i.e., the direction in which the
-coordinate values are increasing), whether up or down, cannot in
-all cases be inferred from the <a class="reference internal" href="../generated/cf.AuxiliaryCoordinate.units.html#cf.AuxiliaryCoordinate.units" title="cf.AuxiliaryCoordinate.units"><code class="xref py py-obj docutils literal notranslate"><span class="pre">units</span></code></a>. The direction of positive
-is useful for applications displaying the data. The <a class="reference internal" href="#cf.AuxiliaryCoordinate.positive" title="cf.AuxiliaryCoordinate.positive"><code class="xref py py-obj docutils literal notranslate"><span class="pre">positive</span></code></a>
-attribute may have the value <code class="docutils literal notranslate"><span class="pre">'up'</span></code> or <code class="docutils literal notranslate"><span class="pre">'down'</span></code> (case
-insensitive).</p>
-<p>For example, if ocean depth coordinates encode the depth of the
-surface as 0 and the depth of 1000 meters as 1000 then the
-<code class="xref py py-obj docutils literal notranslate"><span class="pre">postive</span></code> property will have the value <code class="xref py py-obj docutils literal notranslate"><span class="pre">'down'</span></code>.</p>
-<p><strong>Examples:</strong></p>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">positive</span> <span class="o">=</span> <span class="s1">&#39;up&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">positive</span>
-<span class="go">&#39;up&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="k">del</span> <span class="n">c</span><span class="o">.</span><span class="n">positive</span>
-</pre></div>
-</div>
-<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">set_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">,</span> <span class="s1">&#39;down&#39;</span><span class="p">)</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">get_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">)</span>
-<span class="go">&#39;down&#39; </span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">del_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">)</span>
-</pre></div>
-</div>
-</dd></dl>
-
-</div>
-
-
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-          
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-      </div>
-    <div class="clearer"></div>
-  </div>
-    <div class="footer">
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diff --git a/docs/method/cf.AuxiliaryCoordinate.reference_datetime.html b/docs/method/cf.AuxiliaryCoordinate.reference_datetime.html
deleted file mode 100644
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--- a/docs/method/cf.AuxiliaryCoordinate.reference_datetime.html
+++ /dev/null
@@ -1,112 +0,0 @@
-
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
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-  <div class="section" id="cf-auxiliarycoordinate-reference-datetime">
-<h1>cf.AuxiliaryCoordinate.reference_datetime<a class="headerlink" href="#cf-auxiliarycoordinate-reference-datetime" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.AuxiliaryCoordinate.reference_datetime">
-<code class="descclassname">AuxiliaryCoordinate.</code><code class="descname">reference_datetime</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.AuxiliaryCoordinate.reference_datetime" title="Permalink to this definition">¶</a></dt>
-<dd><p>TODO</p>
-</dd></dl>
-
-</div>
-
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-          rel="nofollow">Page source</a>
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diff --git a/docs/method/cf.Bounds.positive.html b/docs/method/cf.Bounds.positive.html
deleted file mode 100644
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--- a/docs/method/cf.Bounds.positive.html
+++ /dev/null
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-
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-
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-  <div class="section" id="cf-bounds-positive">
-<h1>cf.Bounds.positive<a class="headerlink" href="#cf-bounds-positive" title="Permalink to this headline">¶</a></h1>
-<dl class="method">
-<dt id="cf.Bounds.positive">
-<code class="sig-prename descclassname">Bounds.</code><code class="sig-name descname">positive</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#cf.Bounds.positive" title="Permalink to this definition">¶</a></dt>
-<dd><p>The positive CF property.</p>
-<p>The direction of positive (i.e., the direction in which the
-coordinate values are increasing), whether up or down, cannot in
-all cases be inferred from the <a class="reference internal" href="../attribute/cf.Bounds.units.html#cf.Bounds.units" title="cf.Bounds.units"><code class="xref py py-obj docutils literal notranslate"><span class="pre">units</span></code></a>. The direction of positive
-is useful for applications displaying the data. The <a class="reference internal" href="#cf.Bounds.positive" title="cf.Bounds.positive"><code class="xref py py-obj docutils literal notranslate"><span class="pre">positive</span></code></a>
-attribute may have the value <code class="docutils literal notranslate"><span class="pre">'up'</span></code> or <code class="docutils literal notranslate"><span class="pre">'down'</span></code> (case
-insensitive).</p>
-<p>For example, if ocean depth coordinates encode the depth of the
-surface as 0 and the depth of 1000 meters as 1000 then the
-<code class="xref py py-obj docutils literal notranslate"><span class="pre">postive</span></code> property will have the value <code class="xref py py-obj docutils literal notranslate"><span class="pre">'down'</span></code>.</p>
-<p><strong>Examples:</strong></p>
-<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">positive</span> <span class="o">=</span> <span class="s1">&#39;up&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">positive</span>
-<span class="go">&#39;up&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="k">del</span> <span class="n">c</span><span class="o">.</span><span class="n">positive</span>
-</pre></div>
-</div>
-<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">set_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">,</span> <span class="s1">&#39;down&#39;</span><span class="p">)</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">get_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">)</span>
-<span class="go">&#39;down&#39;</span>
-<span class="gp">&gt;&gt;&gt; </span><span class="n">c</span><span class="o">.</span><span class="n">del_property</span><span class="p">(</span><span class="s1">&#39;positive&#39;</span><span class="p">)</span>
-</pre></div>
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