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<section id="coordinates">
<h1>Coordinates<a class="headerlink" href="#coordinates" title="Permalink to this heading"></a></h1>
<section id="overview">
<h2>Overview<a class="headerlink" href="#overview" title="Permalink to this heading"></a></h2>
<p>Coordinates are used to:</p>
<ol class="arabic simple">
<li><p>Evaluate <a class="reference internal" href="nodes.html"><span class="std std-doc">nodes</span></a> which retrieve and process data</p></li>
<li><p>Define the coordinates of <a class="reference internal" href="nodes.html#datasource"><span class="std std-ref">data sources</span></a></p></li>
</ol>
<p>Podpac Coordinates are modeled after the coords in <a class="reference external" href="http://xarray.pydata.org/en/stable/data-structures.html">xarray</a>,
with some additional restrictions and enhancements. Coordinates are created from a list of coordinate <code class="docutils literal notranslate"><span class="pre">values</span></code> and a corresponding list of <code class="docutils literal notranslate"><span class="pre">dims</span></code>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">podpac</span><span class="o">.</span><span class="n">Coordinates</span><span class="p">(</span><span class="n">values</span><span class="p">,</span> <span class="n">dims</span><span class="o">=</span><span class="n">dims</span><span class="p">,</span> <span class="o">...</span><span class="p">)</span>
</pre></div>
</div>
<p>Unlike xarray, podpac coordinate values are always either <code class="docutils literal notranslate"><span class="pre">float</span></code> or <code class="docutils literal notranslate"><span class="pre">np.datetime64</span></code>. For convenience, podpac
automatically converts datetime strings such as <code class="docutils literal notranslate"><span class="pre">'2018-01-01'</span></code> to <code class="docutils literal notranslate"><span class="pre">np.datetime64</span></code>. In addition, the allowed dimensions
are <code class="docutils literal notranslate"><span class="pre">'lat'</span></code>, <code class="docutils literal notranslate"><span class="pre">'lon'</span></code>, <code class="docutils literal notranslate"><span class="pre">'time'</span></code>, and <code class="docutils literal notranslate"><span class="pre">'alt'</span></code>.</p>
</section>
<section id="coordinate-creation">
<h2>Coordinate Creation<a class="headerlink" href="#coordinate-creation" title="Permalink to this heading"></a></h2>
<section id="unstacked-coordinates">
<h3>Unstacked Coordinates<a class="headerlink" href="#unstacked-coordinates" title="Permalink to this heading"></a></h3>
<p>Unstacked multidimensional coordinates form a grid of points. For example, the following Coordinates contain three dimensions and a total of 24 points.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lat</span> <span class="o">=</span> <span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lon</span> <span class="o">=</span> <span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="mi">40</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">time</span> <span class="o">=</span> <span class="p">[</span><span class="s1">'2018-01-01'</span><span class="p">,</span> <span class="s1">'2018-01-02'</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">Coordinates</span><span class="p">([</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat'</span><span class="p">,</span> <span class="s1">'lon'</span><span class="p">])</span>
<span class="n">Coordinates</span>
<span class="n">lat</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lat</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="n">lon</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lon</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">10.0</span><span class="p">,</span> <span class="mf">40.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">4</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">Coordinates</span><span class="p">([</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">,</span> <span class="n">time</span><span class="p">],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat'</span><span class="p">,</span> <span class="s1">'lon'</span><span class="p">,</span> <span class="s1">'time'</span><span class="p">])</span>
<span class="n">Coordinates</span>
<span class="n">lat</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lat</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="n">lon</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lon</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">10.0</span><span class="p">,</span> <span class="mf">40.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">4</span><span class="p">]</span>
<span class="n">time</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">time</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mi">2018</span><span class="o">-</span><span class="mi">01</span><span class="o">-</span><span class="mi">01</span><span class="p">,</span> <span class="mi">2018</span><span class="o">-</span><span class="mi">01</span><span class="o">-</span><span class="mi">02</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span>
</pre></div>
</div>
<p>You can also create coordinates with just one dimension the same way:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="gp">>>> </span><span class="n">Coordinates</span><span class="p">([</span><span class="n">time</span><span class="p">],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'time'</span><span class="p">])</span>
<span class="go">Coordinates</span>
<span class="go"> time: ArrayCoordinates1d(time): Bounds[2018-01-01, 2018-01-02], N[2]</span>
</pre></div>
</div>
</section>
<section id="stacked-coordinates">
<h3>Stacked Coordinates<a class="headerlink" href="#stacked-coordinates" title="Permalink to this heading"></a></h3>
<p>Coordinates from multiple dimensions can be stacked together in a list (rather than representing a grid).</p>
<p>For example, Coordinates with stacked latitude and longitude contain one point for each (lat, lon) pair. Note
that the name for this stacked dimension is ‘lat_lon’, using an underscore to combine the underlying dimensions.
The following example has a single stacked dimension and a total of 3 points.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lat</span> <span class="o">=</span> <span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lon</span> <span class="o">=</span> <span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span> <span class="o">=</span> <span class="n">Coordinates</span><span class="p">([[</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">]],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat_lon'</span><span class="p">])</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span>
<span class="n">Coordinates</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lat</span><span class="p">]:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lat</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lon</span><span class="p">]:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lon</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">10.0</span><span class="p">,</span> <span class="mf">30.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span><span class="p">[</span><span class="s1">'lat_lon'</span><span class="p">]</span><span class="o">.</span><span class="n">coordinates</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="p">(</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">10.0</span><span class="p">)</span>
</pre></div>
</div>
<p>Coordinates can combine stacked dimensions and unstacked dimensions. For example, in the following Coordinates the <code class="docutils literal notranslate"><span class="pre">(lat,</span> <span class="pre">lon)</span></code> values and the <code class="docutils literal notranslate"><span class="pre">time</span></code> values form a grid of 6 total points.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lat</span> <span class="o">=</span> <span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">lon</span> <span class="o">=</span> <span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">time</span> <span class="o">=</span> <span class="p">[</span><span class="s1">'2018-01-01'</span><span class="p">,</span> <span class="s1">'2018-01-02'</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span> <span class="o">=</span> <span class="n">Coordinates</span><span class="p">([[</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">],</span> <span class="n">time</span><span class="p">],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat_lon'</span><span class="p">,</span> <span class="s1">'time'</span><span class="p">])</span>
<span class="n">Coordinates</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lat</span><span class="p">]:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lat</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lon</span><span class="p">]:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">lon</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">10.0</span><span class="p">,</span> <span class="mf">30.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
<span class="n">time</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">time</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mi">2018</span><span class="o">-</span><span class="mi">01</span><span class="o">-</span><span class="mi">01</span><span class="p">,</span> <span class="mi">2018</span><span class="o">-</span><span class="mi">01</span><span class="o">-</span><span class="mi">02</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span><span class="p">[</span><span class="s1">'lat_lon'</span><span class="p">]</span><span class="o">.</span><span class="n">coordinates</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="p">(</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">10.0</span><span class="p">)</span>
<span class="p">[</span><span class="o">.</span><span class="p">]</span> <span class="n">c</span><span class="p">[</span><span class="s1">'time'</span><span class="p">]</span><span class="o">.</span><span class="n">coordinates</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="n">numpy</span><span class="o">.</span><span class="n">datetime64</span><span class="p">(</span><span class="s1">'2018-01-01'</span><span class="p">)</span>
</pre></div>
</div>
</section>
<section id="uniformly-spaced-coordinates">
<h3>Uniformly-Spaced Coordinates<a class="headerlink" href="#uniformly-spaced-coordinates" title="Permalink to this heading"></a></h3>
<p>Podpac provides two convenience functions <code class="docutils literal notranslate"><span class="pre">crange</span></code> and <code class="docutils literal notranslate"><span class="pre">clinspace</span></code> for creating uniformly-spaced coordinates, similar to the <code class="docutils literal notranslate"><span class="pre">arange</span></code> and <code class="docutils literal notranslate"><span class="pre">linspace</span></code> functions provided by numpy.</p>
<p><strong>Coordinates Range</strong></p>
<p><code class="docutils literal notranslate"><span class="pre">podpac.crange</span></code> creates uniformly-spaced coordinates from a start, stop, and step.</p>
<p>Unlike <code class="docutils literal notranslate"><span class="pre">np.arange</span></code>:</p>
<ul class="simple">
<li><p>string inputs are supported for datetimes and timedeltas</p></li>
<li><p>the stop value will be included in the coordinates if it falls an exact number of steps from the start</p></li>
</ul>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">podpac</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">crange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">array([0., 2., 4., 6.])</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">crange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">8</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">array([0., 2., 4., 6., 8.])</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">crange</span><span class="p">(</span><span class="s1">'2018-01-01'</span><span class="p">,</span> <span class="s1">'2018-03-01'</span><span class="p">,</span> <span class="s1">'1,M'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">array(['2018-01-01', '2018-02-01', '2018-03-01'], dtype='datetime64[D]')</span>
</pre></div>
</div>
<p><strong>Coordinates Linspace</strong></p>
<p><code class="docutils literal notranslate"><span class="pre">podpac.clinspace</span></code> creates uniformly-spaced coordinates from a start, stop, and size.</p>
<p>Unlike <code class="docutils literal notranslate"><span class="pre">np.linspace</span></code>:</p>
<ul class="simple">
<li><p>string inputs are supported for datetimes</p></li>
<li><p>tuple inputs are supported for stacked coordinates</p></li>
</ul>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">podpac</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">clinspace</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">8</span><span class="p">,</span> <span class="mi">5</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">array([0., 2., 4., 6., 8.])</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">clinspace</span><span class="p">(</span><span class="s1">'2018-01-01'</span><span class="p">,</span> <span class="s1">'2018-03-01'</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">array(['2018-01-01', '2018-01-30', '2018-02-28'], dtype='datetime64[D]')</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">podpac</span><span class="o">.</span><span class="n">clinspace</span><span class="p">((</span><span class="mi">0</span><span class="p">,</span> <span class="mi">10</span><span class="p">),</span> <span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">20</span><span class="p">),</span> <span class="mi">3</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">coordinates</span>
<span class="go">MultiIndex(levels=[[0.0, 0.5, 1.0], [10.0, 15.0, 20.0]],</span>
<span class="go"> labels=[[0, 1, 2], [0, 1, 2]])</span>
</pre></div>
</div>
<p>These functions wrap UniformCoordinates1d (see Advanced Usage), which is particularly useful for coordinates with an
extremely large number of points.</p>
</section>
<section id="rotated-coordinates">
<h3>Rotated Coordinates<a class="headerlink" href="#rotated-coordinates" title="Permalink to this heading"></a></h3>
<p>TODO</p>
</section>
<section id="alternate-constructors">
<h3>Alternate Constructors<a class="headerlink" href="#alternate-constructors" title="Permalink to this heading"></a></h3>
<p>Unstacked coordinates can also be created using the <code class="docutils literal notranslate"><span class="pre">Coordinates.grid</span></code> alternate constructor:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="gp">>>> </span><span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">],</span> <span class="n">lon</span><span class="o">=</span><span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="mi">40</span><span class="p">])</span>
<span class="go">Coordinates</span>
<span class="go"> lat: ArrayCoordinates1d(lat): Bounds[0.0, 2.0], N[3]</span>
<span class="go"> lon: ArrayCoordinates1d(lon): Bounds[10.0, 40.0], N[4]</span>
</pre></div>
</div>
<p>Stacked coordinates can be created using the <code class="docutils literal notranslate"><span class="pre">Coordinates.points</span></code> alternate constructor:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="gp">>>> </span><span class="n">Coordinates</span><span class="o">.</span><span class="n">points</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">],</span> <span class="n">lon</span><span class="o">=</span><span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>
<span class="go">Coordinates</span>
<span class="go"> lat_lon[lat]: ArrayCoordinates1d(lat): Bounds[0.0, 2.0], N[3]</span>
<span class="go"> lat_lon[lon]: ArrayCoordinates1d(lon): Bounds[10.0, 30.0], N[3]</span>
</pre></div>
</div>
<p>For convenience, a tuple can be used to generate uniformly-spaced coordinates. If the third item is an integer, it
is interpreted as a size, otherwise it is interpreted as a step. The following will all be equivalent:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">),</span> <span class="n">lon</span><span class="o">=</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">40</span><span class="p">,</span> <span class="mi">4</span><span class="p">))</span>
<span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">),</span> <span class="n">lon</span><span class="o">=</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">40</span><span class="p">,</span> <span class="mf">10.0</span><span class="p">))</span>
<span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="n">clinspace</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">),</span> <span class="n">lon</span><span class="o">=</span><span class="n">clinspace</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">40</span><span class="p">,</span> <span class="mi">4</span><span class="p">))</span>
<span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="n">crange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="n">lon</span><span class="o">=</span><span class="n">crange</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">40</span><span class="p">,</span> <span class="mi">10</span><span class="p">))</span>
</pre></div>
</div>
<p>Note that in Python 3.5 and below, the <code class="docutils literal notranslate"><span class="pre">order</span></code> argument is required to both <code class="docutils literal notranslate"><span class="pre">grid</span></code> and <code class="docutils literal notranslate"><span class="pre">points</span></code></p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">Coordinates</span><span class="o">.</span><span class="n">grid</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">],</span> <span class="n">lon</span><span class="o">=</span><span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">],</span> <span class="n">order</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat'</span><span class="p">,</span> <span class="s1">'lon'</span><span class="p">])</span>
<span class="n">Coordinates</span><span class="o">.</span><span class="n">points</span><span class="p">(</span><span class="n">lat</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">],</span> <span class="n">lon</span><span class="o">=</span><span class="p">[</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">],</span> <span class="n">order</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat'</span><span class="p">,</span> <span class="s1">'lon'</span><span class="p">])</span>
</pre></div>
</div>
</section>
<section id="advanced-usage">
<h3>Advanced Usage<a class="headerlink" href="#advanced-usage" title="Permalink to this heading"></a></h3>
<p>TODO</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">podpac.coordinates</span> <span class="kn">import</span> <span class="n">UniformCoordinates1d</span><span class="p">,</span> <span class="n">ArrayCoordinates1d</span><span class="p">,</span> <span class="n">Coordinates</span><span class="p">,</span> <span class="n">StackedCoordinates</span>
<span class="o">>>></span> <span class="n">lat</span> <span class="o">=</span> <span class="n">UniformCoordinates1d</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="mi">100</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="s1">'lat'</span><span class="p">)</span>
<span class="o">>>></span> <span class="n">lon</span> <span class="o">=</span> <span class="n">UniformCoordinates1d</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="mi">100</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="s1">'lon'</span><span class="p">)</span>
<span class="o">>>></span> <span class="n">time</span> <span class="o">=</span> <span class="n">ArrayCoordinates1d</span><span class="p">([</span><span class="s1">'2018-01-01'</span><span class="p">,</span> <span class="s1">'2018-02-03'</span><span class="p">],</span> <span class="n">name</span><span class="o">=</span><span class="s1">'time'</span><span class="p">)</span>
<span class="o">>>></span> <span class="n">Coordinates</span><span class="p">([</span><span class="n">StackedCoordinates</span><span class="p">([</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">]),</span> <span class="n">time</span><span class="p">])</span>
<span class="n">Coordinates</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lat</span><span class="p">]:</span> <span class="n">UniformCoordinates1d</span><span class="p">(</span><span class="n">lat</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">0.0</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">100</span><span class="p">]</span>
<span class="n">lat_lon</span><span class="p">[</span><span class="n">lon</span><span class="p">]:</span> <span class="n">UniformCoordinates1d</span><span class="p">(</span><span class="n">lon</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mf">10.0</span><span class="p">,</span> <span class="mf">20.0</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">100</span><span class="p">]</span>
<span class="n">time</span><span class="p">:</span> <span class="n">ArrayCoordinates1d</span><span class="p">(</span><span class="n">time</span><span class="p">):</span> <span class="n">Bounds</span><span class="p">[</span><span class="mi">2018</span><span class="o">-</span><span class="mi">01</span><span class="o">-</span><span class="mi">01</span><span class="p">,</span> <span class="mi">2018</span><span class="o">-</span><span class="mi">02</span><span class="o">-</span><span class="mi">03</span><span class="p">],</span> <span class="n">N</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span>
</pre></div>
</div>
</section>
</section>
<section id="coordinate-api">
<h2>Coordinate API<a class="headerlink" href="#coordinate-api" title="Permalink to this heading"></a></h2>
<p>TODO</p>
<p>Coordinates contain some useful properties relating to its dimensions and underlying coordinate values.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">podpac</span> <span class="kn">import</span> <span class="n">Coordinates</span>
<span class="gp">>>> </span><span class="n">c</span> <span class="o">=</span> <span class="n">Coordinates</span><span class="p">([</span><span class="n">lat</span><span class="p">,</span> <span class="n">lon</span><span class="p">,</span> <span class="n">time</span><span class="p">],</span> <span class="n">dims</span><span class="o">=</span><span class="p">[</span><span class="s1">'lat'</span><span class="p">,</span> <span class="s1">'lon'</span><span class="p">,</span> <span class="s1">'time'</span><span class="p">])</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">ndims</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">dims</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">shape</span>
<span class="gp">>>> </span><span class="n">c</span><span class="o">.</span><span class="n">size</span>
</pre></div>
</div>
<p>Coordinates are dict-like. The <code class="docutils literal notranslate"><span class="pre">keys()</span></code>, <code class="docutils literal notranslate"><span class="pre">values()</span></code>, and <code class="docutils literal notranslate"><span class="pre">items()</span></code></p>
</section>
<section id="coordinates-groups">
<h2>Coordinates Groups<a class="headerlink" href="#coordinates-groups" title="Permalink to this heading"></a></h2>
<p>TODO</p>
</section>
</section>
</div>
</div>
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