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<font face="Helvetica, Arial, sans-serif">Dear Gerald,<br>
<br>
Thanks to your suggestion. In trying to give you a sample of expected
output I've tested things more thoroughly (I'm a chemical engineer by
training, so this geo-referenced mapping stuff is all new to me) and it
does appear to be working correctly -- almost.<br>
<br>
my input file, "Desktop/proj" had this:<br>
27.5 0.00<br>
27.5 10.0<br>
27.5 20.0<br>
27.5 30.0<br>
27.58676 26.18728 <br>
<br>
My commands and output from the console:<br>
<br>
neil@neil:~$ proj +proj=tmerc +ellps=WGS84 +lon_0=27 Desktop/proj<br>
55660.46 0.00<br>
54820.34 1105896.37<br>
52324.06 2212444.34<br>
48243.45 3320218.65<br>
58652.24 2897715.76 <br>
<br>
In each case, the magnitudes are correct (as far as I can tell using
other software) but the first column of values should all be negative.<br>
<br>
i.e. Desired output:<br>
</font><font face="Helvetica, Arial, sans-serif">-55660.46 0.00<br>
-54820.34 1105896.37<br>
-52324.06 2212444.34<br>
-48243.45 3320218.65<br>
-58652.24 2897715.76 </font><br>
<font face="Helvetica, Arial, sans-serif"><br>
</font><br>
Gerald I. Evenden wrote:
<blockquote cite="mid:200808111036.52778.geraldi.evenden@gmail.com"
type="cite">
<pre wrap="">On Monday 11 August 2008 4:07:58 am Neil Robinson wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi Gerard,
Thanks for your response. I realise that this isn't a support forum, but
I'm not getting any joy anywhere else and you are clearly very
knowledgeable on this topic
</pre>
</blockquote>
<pre wrap=""><!----> ...
</pre>
<blockquote type="cite">
<pre wrap="">I tried lodging a bug with qgis [1], but they seemed to think the problem
was with proj4 (although, through my ignorance that was my guess, so I
might have planted the seed of that conclusion).
</pre>
<blockquote type="cite">
<pre wrap="">I would just use +proj=tmerc and put some added '-' flags to juggle the
I/O.
But that's somebody else's job as I only work on the library. ;-)
</pre>
</blockquote>
<pre wrap="">I tried this suggestion (I think I did), but negative zero doesn't make any
sense to proj4.
Without adding the '-' flags, this is what I think the parameters need to
be for one of the projections I'm interested in:
+proj=tmerc +ellps=WGS84 +lat_0 +lon_29 +k=1 +towgs84=0,0,0,0,0,0,0
+units=m +no_defs
</pre>
</blockquote>
<pre wrap=""><!---->
Can you give a sample input (lat/lon) and an approximation of what you expect
(without datum conversion which I cannot handle). Under normal circumstances
the above would generate (viewed as a console screen capture):
gie@charon:~$ lproj +proj=tmerc +ellps=WGS84 +lon_0=29
31 45
157693.72 4986890.93
Note; option +towgs84 and +no_defs is not on my software and the other options
are defaulted as you explicitly specified.
The input is longitude(31), latitude(45) and the output is easting(x) and
northing(y) in meters.
What output would you prefer to see?
</pre>
</blockquote>
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