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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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<h1 id="makeellipsecoord">MakeEllipseCoord</h1>
<p>Compute the coordinates of an ellipse placed at a given latitude and longitude.</p>
<h1 id="usage">Usage</h1>
<p>call MakeEllipseCoord (<code>coord</code>, <code>lat</code>, <code>lon</code>, <code>dec</code>, <code>a_theta</code>, <code>b_theta</code>, <code>cinterval</code>, <code>cnum</code>, <code>exitstatus</code>)</p>
<h1 id="parameters">Parameters</h1>
<dl>
<dt><code>coord</code> : output, real*8, dimension(360/<code>cinterval</code>, 2)</dt>
<dd>The latitude (:,1) and longitude (:,2) coordinates of the ellipse in degrees.
</dd>
<dt><code>lat</code> : input, real*8</dt>
<dd>The latitude of the center of the ellipse in degrees.
</dd>
<dt><code>lon</code> : input, real*8</dt>
<dd>The longitude of the center of the ellipse in degrees.
</dd>
<dt><code>dec</code> : input, real*8</dt>
<dd>Rotation angle of the semi-major axis of the ellipse in degrees with respect to local north.
</dd>
<dt><code>a_theta</code> : input, real*8</dt>
<dd>The angular radius of the semi-major axis of the ellipse in degrees.
</dd>
<dt><code>b_theta</code> : input, real*8</dt>
<dd>The angular radius of the semi-minor axis of the ellipse in degrees.
</dd>
<dt><code>cinterval</code> : optional, input, real*8, default = 1</dt>
<dd>Angular spacing in degrees of the output latitude and longitude points. If not present, the default is 1.
</dd>
<dt><code>cnum</code> : optional, output, integer</dt>
<dd>Number of elements in the output arrays.
</dd>
<dt><code>exitstatus</code> : output, optional, integer</dt>
<dd>If present, instead of executing a STOP when an error is encountered, the variable exitstatus will be returned describing the error. 0 = No errors; 1 = Improper dimensions of input array; 2 = Improper bounds for input variable; 3 = Error allocating memory; 4 = File IO error.
</dd>
</dl>
<h1 id="description">Description</h1>
<p><code>MakeEllipseCoord</code> will calculate the (lat, long) coordinates of an ellipse placed on a sphere at position (<code>lat</code>, <code>lon</code>). The semi-major and semi-minor axes, expressed in angular radii in degrees, are given by <code>a_theta</code> and <code>b_theta</code>, respectively. The semimajor axis of the ellipse is initially directed due north, and it is then rotated clockwise by the angle <code>dec</code>. This is useful for plotting ellipses on geographic maps. The first index in the output vectors corresponds to the northern rotated semimajor axis, and subsequent points are arranged in a clockwise manner. Input and output units are in degrees.</p>
<h1 id="see-also">See also</h1>
<p><a href="makecirclecoord.html">makecirclecoord</a></p>
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