<div dir="ltr">Hi Noel, <div><br></div><div>We set up the above definition from following the proj4 definition of geostationary. We have also tried this string: </div><div>Proj("+proj=geos +h=35786023 +a= 6378137.0 +b= 6356752.3141403561 +sweep=y +lon_0=-75 x_0=-.151844 y_0=.151844 +units=meters +no_defs") and still get the same error for the off earth data. </div>
<div><br></div><div>I get these as the output extents:[1e+30, 1e+30, 1e+30, 1e+30] and the error given is this: RuntimeError: tolerance condition error</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">
On Tue, Aug 13, 2013 at 10:43 AM, Noel Zinn (cc) <span dir="ltr"><<a href="mailto:ndzinn@comcast.net" target="_blank">ndzinn@comcast.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div dir="ltr">
<div style="font-size:12pt;font-family:'Calibri'">
<div>Your graphic shows the earth profile as an ellipse, but your proj4 string
sets a and b to the semi-major axis of WGS84 (i.e. a sphere). Why?
-Noel</div>
<div> </div>
<div style="font-size:12pt;font-family:'Calibri'">Noel Zinn,
Principal, Hydrometronics LLC<br><a href="tel:%2B1-832-539-1472" value="+18325391472" target="_blank">+1-832-539-1472</a> (office), <a href="tel:%2B1-281-221-0051" value="+12812210051" target="_blank">+1-281-221-0051</a>
(cell)<br><a href="mailto:noel.zinn@hydrometronics.com" target="_blank">noel.zinn@hydrometronics.com</a> (email)<br><a href="http://www.hydrometronics.com" target="_blank">http://www.hydrometronics.com</a>
(website)<br></div>
<div style="font-style:normal;font-size:small;display:inline;text-decoration:none;font-family:'Calibri';font-weight:normal">
<div style="FONT:10pt tahoma">
<div> </div>
<div style="BACKGROUND:#f5f5f5">
<div><b>From:</b> <a title="kathryn.jablonski@noaa.gov" href="mailto:kathryn.jablonski@noaa.gov" target="_blank">Kathryn Jablonski - NOAA Affiliate</a>
</div>
<div><b>Sent:</b> Tuesday, August 13, 2013 9:38 AM</div><div class="im">
<div><b>To:</b> <a title="proj@lists.maptools.org" href="mailto:proj@lists.maptools.org" target="_blank">PROJ.4 and general Projections
Discussions</a> </div>
<div><b>Subject:</b> Re: [Proj] Proj4 Projection Coordinates for Geostationary
satellitedata</div></div></div></div>
<div> </div></div>
<div style="font-style:normal;font-size:small;display:inline;text-decoration:none;font-family:'Calibri';font-weight:normal"><div><div class="h5">
<div dir="ltr">Thanks Janne.
<div> </div>
<div>We did try drawing a limiting box inside the earth extents to get all valid
data points within, and this works but cuts out data in the edges of the
earth. See the following image: </div>
<div> </div>
<div><img alt="Inline image 1"><br></div>
<div>We still need the data in between the drawn dotted line blue box and the
edge of the earth. The data values in the red shaded off earth areas are
very large (2.14 E9) and these are the values that throw the error. If you
do discard the values in the light red, that is fine but it is throwing an
exception instead, preventing us from proceeding forward. </div>
<div> </div>
<div>Thanks for the support!</div>
<div> </div></div>
<div class="gmail_extra"><br><br>
<div class="gmail_quote">On Tue, Aug 13, 2013 at 3:12 AM, <span dir="ltr"><<a href="mailto:support.mn@elisanet.fi" target="_blank">support.mn@elisanet.fi</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="PADDING-LEFT:1ex;MARGIN:0px 0px 0px 0.8ex;BORDER-LEFT:#ccc 1px solid">Hello,<br><br>we
just discarded all points outside any reasonable area.<br>Another possibility
might be to draw a limiting line (or box)<br>and move all outside points to
that..<br><br>Hope that helps?<br><br>Regards:
Janne.<br><br>----------------------------------------------------------------------------------------<br><br>Kathryn
Jablonski - NOAA Affiliate [<a href="mailto:kathryn.jablonski@noaa.gov" target="_blank">kathryn.jablonski@noaa.gov</a>]
kirjoitti:<br>
<div>
<div>> I am trying to convert geographic coordinates (in degrees
east/north lat<br>> lon) to projected coordinates in meters for
geostationary full disc data<br>> (GVAR Goes East data from CLASS).
To do this, I tried using PyProj/ Proj4<br>> and am running into errors due
to the off earth pixels in the corners.<br>><br>> This is the proj4
string given:<br>> projection_coords = Proj("+proj=geos +h=35774290
+a= 6378137 +b= 6378137<br>> +lon_0=-75 +units=meters +no_defs")<br>>
ll_x, ll_y = projection_coords_geos( LL_y_deg, LL_x_deg, inverse =
False,<br>> errcheck=True)<br>> 'x=%9.3f
y=%11.3f' % (ll_x,ll_y)<br>> ur_x,ur_y =
projection_coords_geos( UR_y_deg, UR_x_deg, inverse =<br>> False,
errcheck=True)<br>> 'x=%9.3f y=%11.3f' % (ur_x,ur_y)<br>><br>>
For full disc geos data I am receiving incorrect (1e30) values for the<br>>
extents and was wondering if anyone has ever run into the same error
or<br>> have a suggestion to correct this.<br>><br>> Also, for
remapping GOES data, should the 'sweep axis' be including in the<br>> Proj
string and set to 'y'?<br>><br>> Thanks in advance for any
suggestions!<br>><br></div></div>>
_______________________________________________<br>> Proj mailing
list<br>> <a href="mailto:Proj@lists.maptools.org" target="_blank">Proj@lists.maptools.org</a><br>> <a href="http://lists.maptools.org/mailman/listinfo/proj" target="_blank">http://lists.maptools.org/mailman/listinfo/proj</a><br>
<br><br>_______________________________________________<br>Proj
mailing list<br><a href="mailto:Proj@lists.maptools.org" target="_blank">Proj@lists.maptools.org</a><br><a href="http://lists.maptools.org/mailman/listinfo/proj" target="_blank">http://lists.maptools.org/mailman/listinfo/proj</a><br>
</blockquote></div>
<div> </div></div>
</div></div><p>
</p><hr><div class="im">
_______________________________________________<br>Proj mailing
list<br><a href="mailto:Proj@lists.maptools.org" target="_blank">Proj@lists.maptools.org</a><br><a href="http://lists.maptools.org/mailman/listinfo/proj" target="_blank">http://lists.maptools.org/mailman/listinfo/proj</a></div>
<p></p></div></div></div></div>
<br>_______________________________________________<br>
Proj mailing list<br>
<a href="mailto:Proj@lists.maptools.org">Proj@lists.maptools.org</a><br>
<a href="http://lists.maptools.org/mailman/listinfo/proj" target="_blank">http://lists.maptools.org/mailman/listinfo/proj</a><br></blockquote></div><br></div>