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| author | PROJ deploybot <proj.bot@proj.bot> | 2022-03-22 20:00:06 +0000 |
|---|---|---|
| committer | PROJ deploybot <proj.bot@proj.bot> | 2022-03-22 20:00:06 +0000 |
| commit | a3f43744feec86272fe532124679d3a013ef9a8c (patch) | |
| tree | 27e4198db6011e3097eb7bcfe7197684aba7583a /operations/projections/omerc.html | |
| download | PROJ-gh-pages.tar.gz PROJ-gh-pages.zip | |
update with results of commit https://github.com/OSGeo/PROJ/commit/53c07a8bd211b7aee4bc07a9c6726005504b7181gh-pages
Diffstat (limited to 'operations/projections/omerc.html')
| -rw-r--r-- | operations/projections/omerc.html | 496 |
1 files changed, 496 insertions, 0 deletions
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+<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 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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> +</ul> +</li> +<li class="toctree-l2"><a class="reference internal" href="../conversions/index.html">Conversions</a></li> +<li class="toctree-l2"><a class="reference internal" href="../transformations/index.html">Transformations</a></li> +<li class="toctree-l2"><a class="reference internal" href="../pipeline.html">The pipeline operator</a></li> +<li class="toctree-l2"><a class="reference internal" href="../operations_computation.html">Computation of coordinate operations between two CRS</a></li> +</ul> +</li> +<li class="toctree-l1"><a class="reference internal" href="../../resource_files.html">Resource files</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../geodesic.html">Geodesic calculations</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../development/index.html">Development</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../specifications/index.html">Specifications</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../community/index.html">Community</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../faq.html">FAQ</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../glossary.html">Glossary</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../zreferences.html">References</a></li> +</ul> + + </div> + </div> + </nav> + + <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap"><nav class="wy-nav-top" aria-label="Mobile navigation menu" style="background: #353130" > + <i data-toggle="wy-nav-top" class="fa fa-bars"></i> + <a href="../../index.html">PROJ</a> + </nav> + + <div class="wy-nav-content"> + <div class="rst-content"> + <div role="navigation" aria-label="Page navigation"> + <ul class="wy-breadcrumbs"> + <li><a href="../../index.html" class="icon icon-home"></a> »</li> + <li><a href="../index.html">Coordinate operations</a> »</li> + <li><a href="index.html">Projections</a> »</li> + <li>Oblique Mercator</li> + <li class="wy-breadcrumbs-aside"> + <a href="https://github.com/OSGeo/PROJ/edit/8.2/docs/source/operations/projections/omerc.rst" class="fa fa-github"> Edit on GitHub</a> + </li> + </ul><div class="rst-breadcrumbs-buttons" role="navigation" aria-label="Sequential page navigation"> + <a href="oea.html" class="btn btn-neutral float-left" title="Oblated Equal Area" accesskey="p"><span class="fa fa-arrow-circle-left" aria-hidden="true"></span> Previous</a> + <a href="ortel.html" class="btn btn-neutral float-right" title="Ortelius Oval" accesskey="n">Next <span class="fa fa-arrow-circle-right" aria-hidden="true"></span></a> + </div> + <hr/> +</div> + <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article"> + <div itemprop="articleBody"> + + <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> + + + </div> + </div> + <footer><div class="rst-footer-buttons" role="navigation" aria-label="Footer"> + <a href="oea.html" class="btn btn-neutral float-left" title="Oblated Equal Area" accesskey="p" rel="prev"><span class="fa fa-arrow-circle-left" aria-hidden="true"></span> Previous</a> + <a href="ortel.html" class="btn btn-neutral float-right" title="Ortelius Oval" accesskey="n" rel="next">Next <span class="fa fa-arrow-circle-right" aria-hidden="true"></span></a> + </div> + + <hr/> + + <div role="contentinfo"> + <p>© Copyright 1983-2022. + <span class="lastupdated">Last updated on 22 Mar 2022. + </span></p> + </div> + + Built with <a href="https://www.sphinx-doc.org/">Sphinx</a> using a + <a href="https://github.com/readthedocs/sphinx_rtd_theme">theme</a> + provided by <a href="https://readthedocs.org">Read the Docs</a>. + + +</footer> + </div> + </div> + </section> + </div> + <script> + jQuery(function () { + SphinxRtdTheme.Navigation.enable(true); + }); + </script> + +</body> +</html>
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