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<li class="toctree-l1"><a class="reference internal" href="../../about.html">About</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../../download.html">Download</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../../apps/index.html">Applications</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="../index.html">Coordinate operations</a><ul class="current">
<li class="toctree-l2 current"><a class="reference internal" href="index.html">Projections</a><ul class="current">
<li class="toctree-l3"><a class="reference internal" href="adams_hemi.html">Adams Hemisphere in a Square</a></li>
<li class="toctree-l3"><a class="reference internal" href="adams_ws1.html">Adams World in a Square I</a></li>
<li class="toctree-l3"><a class="reference internal" href="adams_ws2.html">Adams World in a Square II</a></li>
<li class="toctree-l3"><a class="reference internal" href="aea.html">Albers Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="aeqd.html">Azimuthal Equidistant</a></li>
<li class="toctree-l3"><a class="reference internal" href="airy.html">Airy</a></li>
<li class="toctree-l3"><a class="reference internal" href="aitoff.html">Aitoff</a></li>
<li class="toctree-l3"><a class="reference internal" href="alsk.html">Modified Stereographic of Alaska</a></li>
<li class="toctree-l3"><a class="reference internal" href="apian.html">Apian Globular I</a></li>
<li class="toctree-l3"><a class="reference internal" href="august.html">August Epicycloidal</a></li>
<li class="toctree-l3"><a class="reference internal" href="bacon.html">Bacon Globular</a></li>
<li class="toctree-l3"><a class="reference internal" href="bertin1953.html">Bertin 1953</a></li>
<li class="toctree-l3"><a class="reference internal" href="bipc.html">Bipolar conic of western hemisphere</a></li>
<li class="toctree-l3"><a class="reference internal" href="boggs.html">Boggs Eumorphic</a></li>
<li class="toctree-l3"><a class="reference internal" href="bonne.html">Bonne (Werner lat_1=90)</a></li>
<li class="toctree-l3"><a class="reference internal" href="calcofi.html">Cal Coop Ocean Fish Invest Lines/Stations</a></li>
<li class="toctree-l3"><a class="reference internal" href="cass.html">Cassini (Cassini-Soldner)</a></li>
<li class="toctree-l3"><a class="reference internal" href="cc.html">Central Cylindrical</a></li>
<li class="toctree-l3"><a class="reference internal" href="ccon.html">Central Conic</a></li>
<li class="toctree-l3"><a class="reference internal" href="cea.html">Equal Area Cylindrical</a></li>
<li class="toctree-l3"><a class="reference internal" href="chamb.html">Chamberlin Trimetric</a></li>
<li class="toctree-l3"><a class="reference internal" href="collg.html">Collignon</a></li>
<li class="toctree-l3"><a class="reference internal" href="col_urban.html">Colombia Urban</a></li>
<li class="toctree-l3"><a class="reference internal" href="comill.html">Compact Miller</a></li>
<li class="toctree-l3"><a class="reference internal" href="crast.html">Craster Parabolic (Putnins P4)</a></li>
<li class="toctree-l3"><a class="reference internal" href="denoy.html">Denoyer Semi-Elliptical</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck1.html">Eckert I</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck2.html">Eckert II</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck3.html">Eckert III</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck4.html">Eckert IV</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck5.html">Eckert V</a></li>
<li class="toctree-l3"><a class="reference internal" href="eck6.html">Eckert VI</a></li>
<li class="toctree-l3"><a class="reference internal" href="eqc.html">Equidistant Cylindrical (Plate Carrée)</a></li>
<li class="toctree-l3"><a class="reference internal" href="eqdc.html">Equidistant Conic</a></li>
<li class="toctree-l3"><a class="reference internal" href="eqearth.html">Equal Earth</a></li>
<li class="toctree-l3"><a class="reference internal" href="euler.html">Euler</a></li>
<li class="toctree-l3"><a class="reference internal" href="fahey.html">Fahey</a></li>
<li class="toctree-l3"><a class="reference internal" href="fouc.html">Foucaut</a></li>
<li class="toctree-l3"><a class="reference internal" href="fouc_s.html">Foucaut Sinusoidal</a></li>
<li class="toctree-l3"><a class="reference internal" href="gall.html">Gall (Gall Stereographic)</a></li>
<li class="toctree-l3"><a class="reference internal" href="geos.html">Geostationary Satellite View</a></li>
<li class="toctree-l3"><a class="reference internal" href="gins8.html">Ginsburg VIII (TsNIIGAiK)</a></li>
<li class="toctree-l3"><a class="reference internal" href="gn_sinu.html">General Sinusoidal Series</a></li>
<li class="toctree-l3"><a class="reference internal" href="gnom.html">Gnomonic</a></li>
<li class="toctree-l3"><a class="reference internal" href="goode.html">Goode Homolosine</a></li>
<li class="toctree-l3"><a class="reference internal" href="gs48.html">Modified Stereographic of 48 U.S.</a></li>
<li class="toctree-l3"><a class="reference internal" href="gs50.html">Modified Stereographic of 50 U.S.</a></li>
<li class="toctree-l3"><a class="reference internal" href="guyou.html">Guyou</a></li>
<li class="toctree-l3"><a class="reference internal" href="hammer.html">Hammer & Eckert-Greifendorff</a></li>
<li class="toctree-l3"><a class="reference internal" href="hatano.html">Hatano Asymmetrical Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="healpix.html">HEALPix</a></li>
<li class="toctree-l3"><a class="reference internal" href="rhealpix.html">rHEALPix</a></li>
<li class="toctree-l3"><a class="reference internal" href="igh.html">Interrupted Goode Homolosine</a></li>
<li class="toctree-l3"><a class="reference internal" href="igh_o.html">Interrupted Goode Homolosine (Oceanic View)</a></li>
<li class="toctree-l3"><a class="reference internal" href="imw_p.html">International Map of the World Polyconic</a></li>
<li class="toctree-l3"><a class="reference internal" href="isea.html">Icosahedral Snyder Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="kav5.html">Kavrayskiy V</a></li>
<li class="toctree-l3"><a class="reference internal" href="kav7.html">Kavrayskiy VII</a></li>
<li class="toctree-l3"><a class="reference internal" href="krovak.html">Krovak</a></li>
<li class="toctree-l3"><a class="reference internal" href="labrd.html">Laborde</a></li>
<li class="toctree-l3"><a class="reference internal" href="laea.html">Lambert Azimuthal Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="lagrng.html">Lagrange</a></li>
<li class="toctree-l3"><a class="reference internal" href="larr.html">Larrivee</a></li>
<li class="toctree-l3"><a class="reference internal" href="lask.html">Laskowski</a></li>
<li class="toctree-l3"><a class="reference internal" href="lcc.html">Lambert Conformal Conic</a></li>
<li class="toctree-l3"><a class="reference internal" href="lcca.html">Lambert Conformal Conic Alternative</a></li>
<li class="toctree-l3"><a class="reference internal" href="leac.html">Lambert Equal Area Conic</a></li>
<li class="toctree-l3"><a class="reference internal" href="lee_os.html">Lee Oblated Stereographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="loxim.html">Loximuthal</a></li>
<li class="toctree-l3"><a class="reference internal" href="lsat.html">Space oblique for LANDSAT</a></li>
<li class="toctree-l3"><a class="reference internal" href="mbt_s.html">McBryde-Thomas Flat-Polar Sine (No. 1)</a></li>
<li class="toctree-l3"><a class="reference internal" href="mbt_fps.html">McBryde-Thomas Flat-Pole Sine (No. 2)</a></li>
<li class="toctree-l3"><a class="reference internal" href="mbtfpp.html">McBride-Thomas Flat-Polar Parabolic</a></li>
<li class="toctree-l3"><a class="reference internal" href="mbtfpq.html">McBryde-Thomas Flat-Polar Quartic</a></li>
<li class="toctree-l3"><a class="reference internal" href="mbtfps.html">McBryde-Thomas Flat-Polar Sinusoidal</a></li>
<li class="toctree-l3"><a class="reference internal" href="merc.html">Mercator</a></li>
<li class="toctree-l3"><a class="reference internal" href="mil_os.html">Miller Oblated Stereographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="mill.html">Miller Cylindrical</a></li>
<li class="toctree-l3"><a class="reference internal" href="misrsom.html">Space oblique for MISR</a></li>
<li class="toctree-l3"><a class="reference internal" href="moll.html">Mollweide</a></li>
<li class="toctree-l3"><a class="reference internal" href="murd1.html">Murdoch I</a></li>
<li class="toctree-l3"><a class="reference internal" href="murd2.html">Murdoch II</a></li>
<li class="toctree-l3"><a class="reference internal" href="murd3.html">Murdoch III</a></li>
<li class="toctree-l3"><a class="reference internal" href="natearth.html">Natural Earth</a></li>
<li class="toctree-l3"><a class="reference internal" href="natearth2.html">Natural Earth II</a></li>
<li class="toctree-l3"><a class="reference internal" href="nell.html">Nell</a></li>
<li class="toctree-l3"><a class="reference internal" href="nell_h.html">Nell-Hammer</a></li>
<li class="toctree-l3"><a class="reference internal" href="nicol.html">Nicolosi Globular</a></li>
<li class="toctree-l3"><a class="reference internal" href="nsper.html">Near-sided perspective</a></li>
<li class="toctree-l3"><a class="reference internal" href="nzmg.html">New Zealand Map Grid</a></li>
<li class="toctree-l3"><a class="reference internal" href="ob_tran.html">General Oblique Transformation</a></li>
<li class="toctree-l3"><a class="reference internal" href="ocea.html">Oblique Cylindrical Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="oea.html">Oblated Equal Area</a></li>
<li class="toctree-l3 current"><a class="current reference internal" href="#">Oblique Mercator</a><ul>
<li class="toctree-l4"><a class="reference internal" href="#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="#parameters">Parameters</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="ortel.html">Ortelius Oval</a></li>
<li class="toctree-l3"><a class="reference internal" href="ortho.html">Orthographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="patterson.html">Patterson</a></li>
<li class="toctree-l3"><a class="reference internal" href="pconic.html">Perspective Conic</a></li>
<li class="toctree-l3"><a class="reference internal" href="peirce_q.html">Peirce Quincuncial</a></li>
<li class="toctree-l3"><a class="reference internal" href="poly.html">Polyconic (American)</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp1.html">Putnins P1</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp2.html">Putnins P2</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp3.html">Putnins P3</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp3p.html">Putnins P3’</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp4p.html">Putnins P4’</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp5.html">Putnins P5</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp5p.html">Putnins P5’</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp6.html">Putnins P6</a></li>
<li class="toctree-l3"><a class="reference internal" href="putp6p.html">Putnins P6’</a></li>
<li class="toctree-l3"><a class="reference internal" href="qua_aut.html">Quartic Authalic</a></li>
<li class="toctree-l3"><a class="reference internal" href="qsc.html">Quadrilateralized Spherical Cube</a></li>
<li class="toctree-l3"><a class="reference internal" href="robin.html">Robinson</a></li>
<li class="toctree-l3"><a class="reference internal" href="rouss.html">Roussilhe Stereographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="rpoly.html">Rectangular Polyconic</a></li>
<li class="toctree-l3"><a class="reference internal" href="s2.html">S2</a></li>
<li class="toctree-l3"><a class="reference internal" href="sch.html">Spherical Cross-track Height</a></li>
<li class="toctree-l3"><a class="reference internal" href="sinu.html">Sinusoidal (Sanson-Flamsteed)</a></li>
<li class="toctree-l3"><a class="reference internal" href="somerc.html">Swiss Oblique Mercator</a></li>
<li class="toctree-l3"><a class="reference internal" href="stere.html">Stereographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="sterea.html">Oblique Stereographic Alternative</a></li>
<li class="toctree-l3"><a class="reference internal" href="gstmerc.html">Gauss-Schreiber Transverse Mercator (aka Gauss-Laborde Reunion)</a></li>
<li class="toctree-l3"><a class="reference internal" href="tcc.html">Transverse Central Cylindrical</a></li>
<li class="toctree-l3"><a class="reference internal" href="tcea.html">Transverse Cylindrical Equal Area</a></li>
<li class="toctree-l3"><a class="reference internal" href="times.html">Times</a></li>
<li class="toctree-l3"><a class="reference internal" href="tissot.html">Tissot</a></li>
<li class="toctree-l3"><a class="reference internal" href="tmerc.html">Transverse Mercator</a></li>
<li class="toctree-l3"><a class="reference internal" href="tobmerc.html">Tobler-Mercator</a></li>
<li class="toctree-l3"><a class="reference internal" href="tpeqd.html">Two Point Equidistant</a></li>
<li class="toctree-l3"><a class="reference internal" href="tpers.html">Tilted perspective</a></li>
<li class="toctree-l3"><a class="reference internal" href="ups.html">Universal Polar Stereographic</a></li>
<li class="toctree-l3"><a class="reference internal" href="urm5.html">Urmaev V</a></li>
<li class="toctree-l3"><a class="reference internal" href="urmfps.html">Urmaev Flat-Polar Sinusoidal</a></li>
<li class="toctree-l3"><a class="reference internal" href="utm.html">Universal Transverse Mercator (UTM)</a></li>
<li class="toctree-l3"><a class="reference internal" href="vandg.html">van der Grinten (I)</a></li>
<li class="toctree-l3"><a class="reference internal" href="vandg2.html">van der Grinten II</a></li>
<li class="toctree-l3"><a class="reference internal" href="vandg3.html">van der Grinten III</a></li>
<li class="toctree-l3"><a class="reference internal" href="vandg4.html">van der Grinten IV</a></li>
<li class="toctree-l3"><a class="reference internal" href="vitk1.html">Vitkovsky I</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag1.html">Wagner I (Kavrayskiy VI)</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag2.html">Wagner II</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag3.html">Wagner III</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag4.html">Wagner IV</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag5.html">Wagner V</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag6.html">Wagner VI</a></li>
<li class="toctree-l3"><a class="reference internal" href="wag7.html">Wagner VII</a></li>
<li class="toctree-l3"><a class="reference internal" href="webmerc.html">Web Mercator / Pseudo Mercator</a></li>
<li class="toctree-l3"><a class="reference internal" href="weren.html">Werenskiold I</a></li>
<li class="toctree-l3"><a class="reference internal" href="wink1.html">Winkel I</a></li>
<li class="toctree-l3"><a class="reference internal" href="wink2.html">Winkel II</a></li>
<li class="toctree-l3"><a class="reference internal" href="wintri.html">Winkel Tripel</a></li>
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<li>Oblique Mercator</li>
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<section id="oblique-mercator">
<span id="omerc"></span><h1>Oblique Mercator<a class="headerlink" href="#oblique-mercator" title="Permalink to this headline">¶</a></h1>
<p>The Oblique Mercator projection is a cylindrical map projection that closes the
gap between the Mercator and the Transverse Mercator projections.</p>
<table class="docutils align-default">
<colgroup>
<col style="width: 27%" />
<col style="width: 73%" />
</colgroup>
<tbody>
<tr class="row-odd"><td><p><strong>Classification</strong></p></td>
<td><p>Conformal cylindrical</p></td>
</tr>
<tr class="row-even"><td><p><strong>Available forms</strong></p></td>
<td><p>Forward and inverse, spherical and ellipsoidal</p></td>
</tr>
<tr class="row-odd"><td><p><strong>Defined area</strong></p></td>
<td><p>Global, but reasonably accurate only within 15 degrees
of the oblique central line</p></td>
</tr>
<tr class="row-even"><td><p><strong>Alias</strong></p></td>
<td><p>omerc</p></td>
</tr>
<tr class="row-odd"><td><p><strong>Domain</strong></p></td>
<td><p>2D</p></td>
</tr>
<tr class="row-even"><td><p><strong>Input type</strong></p></td>
<td><p>Geodetic coordinates</p></td>
</tr>
<tr class="row-odd"><td><p><strong>Output type</strong></p></td>
<td><p>Projected coordinates</p></td>
</tr>
</tbody>
</table>
<figure class="align-center" id="id3">
<a class="reference internal image-reference" href="../../_images/omerc.png"><img alt="Oblique Mercator" src="../../_images/omerc.png" style="width: 500px;" /></a>
<figcaption>
<p><span class="caption-text">proj-string: <code class="docutils literal notranslate"><span class="pre">+proj=omerc</span> <span class="pre">+lat_1=45</span> <span class="pre">+lat_2=55</span></code></span><a class="headerlink" href="#id3" title="Permalink to this image">¶</a></p>
</figcaption>
</figure>
<p>Figuratively, the cylinder used for developing the Mercator projection touches
the planet along the Equator, while that of the Transverse Mercator touches the
planet along a meridian, i.e. along a line perpendicular to the Equator.</p>
<p>The cylinder for the Oblique Mercator, however, touches the planet along a line
at an arbitrary angle with the Equator. Hence, the Oblique Mercator projection
is useful for mapping areas having their greatest extent along a direction that
is neither north-south, nor east-west.</p>
<p>The Mercator and the Transverse Mercator projections are both limiting forms of
the Oblique Mercator: The Mercator projection is equivalent to an Oblique Mercator
with central line along the Equator, while the Transverse Mercator is equivalent
to an Oblique Mercator with central line along a meridian.</p>
<p>For the sphere, the construction of the Oblique Mercator projection can be
imagined as “tilting the cylinder of a plain Mercator projection”,
so the cylinder, instead of touching the equator, touches an arbitrary great circle
on the sphere. The great circle is defined by the tilt angle of the central line,
hence putting land masses along that great circle near the centre of the map,
where the Equator would go in the plain Mercator case.</p>
<p>The ellipsoidal case, developed by Hotine, and refined by Snyder <span id="id1">[<a class="reference internal" href="../../zreferences.html#id37" title="Snyder, J. P. Map projections — A working manual. Professional Paper 1395, U.S. Geological Survey, 1987. doi:10.3133/pp1395.">Snyder1987</a>]</span>
is more complex, involving initial steps projecting from the ellipsoid to another
curved surface, the “aposphere”, then projection from the aposphere to the skew
uv-plane, before finally rectifying the skew uv-plane onto the map XY plane.</p>
<section id="usage">
<h2>Usage<a class="headerlink" href="#usage" title="Permalink to this headline">¶</a></h2>
<p>The tilt angle (azimuth) of the central line can be given in two different ways.
In the first case, the azimuth is given directly, using the option <a class="reference internal" href="urm5.html#cmdoption-arg-alpha"><code class="xref std std-option docutils literal notranslate"><span class="pre">+alpha</span></code></a>
and defining the centre of projection using the options <a class="reference internal" href="#cmdoption-arg-lonc"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lonc</span></code></a> and
<a class="reference internal" href="tpers.html#cmdoption-arg-lat_0"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lat_0</span></code></a>.
In the second case, the azimuth is given indirectly by specifying two points on
the central line, using the options
<a class="reference internal" href="wintri.html#cmdoption-arg-lat_1"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lat_1</span></code></a>, <a class="reference internal" href="tpeqd.html#cmdoption-arg-lon_1"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lon_1</span></code></a>, <a class="reference internal" href="vitk1.html#cmdoption-arg-lat_2"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lat_2</span></code></a>, and <a class="reference internal" href="tpeqd.html#cmdoption-arg-lon_2"><code class="xref std std-option docutils literal notranslate"><span class="pre">+lon_2</span></code></a>.</p>
<p>Example: Verify that the Mercator projection is a limiting form of the Oblique
Mercator</p>
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>$ echo 12 55 | proj +proj=merc +ellps=GRS80
1335833.89 7326837.71
$ echo 12 55 | proj +proj=omerc +lonc=0 +alpha=90 +ellps=GRS80
1335833.89 7326837.71
</pre></div>
</div>
<p>Example: Second case - indirectly given azimuth</p>
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>$ echo 12 55 | proj +proj=omerc +lon_1=-1 +lat_1=1 +lon_2=0 +lat_2=0 +ellps=GRS80
349567.57 6839490.50
</pre></div>
</div>
<p>Example: An approximation of the Danish “System 34” from <span id="id2">[<a class="reference internal" href="../../zreferences.html#id30" title="Rittri, M. New omerc approximations of Denmark System 34. e-mail, 2012. URL: https://lists.osgeo.org/pipermail/proj/2012-June/005926.html.">Rittri2012</a>]</span></p>
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>$ echo 10.536498003 56.229892362 | proj +proj=omerc +axis=wnu +lonc=9.46 +lat_0=56.13333333 +x_0=-266906.229 +y_0=189617.957 +k=0.9999537 +alpha=-0.76324 +gamma=0 +ellps=GRS80
200000.13 199999.89
</pre></div>
</div>
<p>The input coordinate represents the System 34 datum point “Agri Bavnehoj”, with coordinates
(200000, 200000) by definition. So at the datum point, the approximation is off by about 17 cm.
This use case represents a datum shift from a cylinder projection on an old, slightly
misaligned datum, to a similar projection on a modern datum.</p>
</section>
<section id="parameters">
<h2>Parameters<a class="headerlink" href="#parameters" title="Permalink to this headline">¶</a></h2>
<section id="central-point-and-azimuth-method">
<h3>Central point and azimuth method<a class="headerlink" href="#central-point-and-azimuth-method" title="Permalink to this headline">¶</a></h3>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-alpha">
<span class="sig-name descname"><span class="pre">+alpha</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-alpha" title="Permalink to this definition">¶</a></dt>
<dd><p>Azimuth of centerline clockwise from north at the center point of the line.
If <a class="reference internal" href="#cmdoption-arg-gamma"><code class="xref std std-option docutils literal notranslate"><span class="pre">+gamma</span></code></a> is not given then <a class="reference internal" href="urm5.html#cmdoption-arg-alpha"><code class="xref std std-option docutils literal notranslate"><span class="pre">+alpha</span></code></a> determines the value of
<a class="reference internal" href="#cmdoption-arg-gamma"><code class="xref std std-option docutils literal notranslate"><span class="pre">+gamma</span></code></a>.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-gamma">
<span class="sig-name descname"><span class="pre">+gamma</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-gamma" title="Permalink to this definition">¶</a></dt>
<dd><p>Azimuth of centerline clockwise from north of the rectified
bearing of centre line. If <a class="reference internal" href="urm5.html#cmdoption-arg-alpha"><code class="xref std std-option docutils literal notranslate"><span class="pre">+alpha</span></code></a> is not given, then
<a class="reference internal" href="#cmdoption-arg-gamma"><code class="xref std std-option docutils literal notranslate"><span class="pre">+gamma</span></code></a> is used to determine <a class="reference internal" href="urm5.html#cmdoption-arg-alpha"><code class="xref std std-option docutils literal notranslate"><span class="pre">+alpha</span></code></a>.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lonc">
<span class="sig-name descname"><span class="pre">+lonc</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lonc" title="Permalink to this definition">¶</a></dt>
<dd><p>Longitude of the central point.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lat_0">
<span id="cmdoption-arg-lat-0"></span><span class="sig-name descname"><span class="pre">+lat_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lat_0" title="Permalink to this definition">¶</a></dt>
<dd><p>Latitude of the central point.</p>
</dd></dl>
</section>
<section id="two-point-method">
<h3>Two point method<a class="headerlink" href="#two-point-method" title="Permalink to this headline">¶</a></h3>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lon_1">
<span id="cmdoption-arg-lon-1"></span><span class="sig-name descname"><span class="pre">+lon_1</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lon_1" title="Permalink to this definition">¶</a></dt>
<dd><p>Longitude of first point.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lat_1">
<span id="cmdoption-arg-lat-1"></span><span class="sig-name descname"><span class="pre">+lat_1</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lat_1" title="Permalink to this definition">¶</a></dt>
<dd><p>Latitude of first point.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lon_2">
<span id="cmdoption-arg-lon-2"></span><span class="sig-name descname"><span class="pre">+lon_2</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lon_2" title="Permalink to this definition">¶</a></dt>
<dd><p>Longitude of second point.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lat_2">
<span id="cmdoption-arg-lat-2"></span><span class="sig-name descname"><span class="pre">+lat_2</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lat_2" title="Permalink to this definition">¶</a></dt>
<dd><p>Latitude of second point.</p>
</dd></dl>
</section>
<section id="optional">
<h3>Optional<a class="headerlink" href="#optional" title="Permalink to this headline">¶</a></h3>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-no_rot">
<span id="cmdoption-arg-no-rot"></span><span class="sig-name descname"><span class="pre">+no_rot</span></span><span class="sig-prename descclassname"></span><a class="headerlink" href="#cmdoption-arg-no_rot" title="Permalink to this definition">¶</a></dt>
<dd><p>No rectification (not “no rotation” as one may well assume).
Do not take the last step from the skew uv-plane to the map
XY plane.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This option is probably only marginally useful, but remains for (mostly) historical reasons.</p>
</div>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-no_off">
<span id="cmdoption-arg-no-off"></span><span class="sig-name descname"><span class="pre">+no_off</span></span><span class="sig-prename descclassname"></span><a class="headerlink" href="#cmdoption-arg-no_off" title="Permalink to this definition">¶</a></dt>
<dd><p>Do not offset origin to center of projection.</p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-k_0">
<span id="cmdoption-arg-k-0"></span><span class="sig-name descname"><span class="pre">+k_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-k_0" title="Permalink to this definition">¶</a></dt>
<dd><p>Scale factor. Determines scale factor used in the projection.</p>
<p><em>Defaults to 1.0.</em></p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-lon_0">
<span id="cmdoption-arg-lon-0"></span><span class="sig-name descname"><span class="pre">+lon_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lon_0" title="Permalink to this definition">¶</a></dt>
<dd><p>Longitude of projection center.</p>
<p><em>Defaults to 0.0.</em></p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-x_0">
<span id="cmdoption-arg-x-0"></span><span class="sig-name descname"><span class="pre">+x_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-x_0" title="Permalink to this definition">¶</a></dt>
<dd><p>False easting.</p>
<p><em>Defaults to 0.0.</em></p>
</dd></dl>
<dl class="std option">
<dt class="sig sig-object std" id="cmdoption-arg-y_0">
<span id="cmdoption-arg-y-0"></span><span class="sig-name descname"><span class="pre">+y_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-y_0" title="Permalink to this definition">¶</a></dt>
<dd><p>False northing.</p>
<p><em>Defaults to 0.0.</em></p>
</dd></dl>
</section>
</section>
</section>
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