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<div class="moz-cite-prefix"><font face="Times New Roman">The normal
convention for surveyors is "name,y,x". - which will be 1c.<br>
<br>
However, that being said, the nature of the coordinate is such
that one can always tell which is the Y and which is the X.<br>
<br>
</font>
<pre class="moz-signature" cols="72">Peter Newmarch
Professional Land Surveyor
4Y GeoInformatics Pty Ltd
Tel : +27 31 5642856
Fax : +27 31 5643074
Mobile : +27 82 5705859
eMail : <a class="moz-txt-link-abbreviated" href="mailto:newmarch@land-surveyors.com">newmarch@land-surveyors.com</a> </pre>
On 2013/09/03 02:16 PM, Gavin Fleming wrote:<br>
</div>
<blockquote cite="mid:5225D32A.50502@afrispatial.co.za" type="cite">Hi
all
<br>
<br>
We are adding some predefined north-oriented SACRS definitions to
QGIS so that we can all easily use the normal "LO" GIS data and
not have to 'roll our own' custom CRS definitions, which should
make everyone's lives easier.
<br>
<br>
The proj4 South-oriented (TMSO) definitions from the EPSG that are
in QGIS 2 (all the 'Lo' Hartebeesthoek and Cape ones) are correct
according to the EPSG but I would like to establish whether
everyone follows the EPSG axis-order convention in South Africa.
If the norm is to NOT follow the axis order conventions, then the
proj4 definitions need to be altered.
<br>
<br>
1. Look at the alternatives for the point below. Say whether you
consider c or d to represent how you obtain and use TMSO
coordinates:
<br>
<br>
a. Here is a WKT point in EPSG:4326
<br>
<br>
POINT(23 -28) Axis order is x,y
<br>
<br>
b. This is the same point in what we GIS users in SA would call
colloquially 'LO23' (i.e. north facing SACRS)
<br>
<br>
POINT(-0.0000000003128453 -3098441.7473872434347868) Axis order
is x,y
<br>
<br>
c. This is the same point in EPSG:2050 (SACRS) with EPSG
axis-order convention (y,x)
<br>
<br>
POINT(0.0000000003128453 3098441.7473872434347868) Axis order is
y,x
<br>
<br>
d. This is the same point in EPSG:2050 (SACRS) with what I think
is South African axis-order convention (x,y)
<br>
<br>
POINT(3098441.7473872434347868 0.0000000003128453) Axis order is
x,y
<br>
<br>
2. Can anyone tell me what axis order ArcGIS expects TMSO
coordinates to be in?
<br>
<br>
3. Please send a small sample of data that you *know* is in TMSO.
e.g. some raw land surveyors data.
<br>
<br>
If you've read this far I'd be grateful for a quick response to 1,
2 and 3.
<br>
<br>
</blockquote>
<br>
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