[GRASS-SVN] r38818 - grass/trunk/lib/gis

[svn_grass at osgeo.org]

Author: hamish
Date: 2009-08-21 10:39:25 -0400 (Fri, 21 Aug 2009)
New Revision: 38818

Modified:
   grass/trunk/lib/gis/datumtransform.table
Log:
explain why terms don't match ref URL

Modified: grass/trunk/lib/gis/datumtransform.table
===================================================================
--- grass/trunk/lib/gis/datumtransform.table	2009-08-21 14:24:35 UTC (rev 38817)
+++ grass/trunk/lib/gis/datumtransform.table	2009-08-21 14:39:25 UTC (rev 38818)
@@ -85,6 +85,7 @@
 # http://www.linz.govt.nz/geodetic/conversion-coordinates/geodetic-datum-conversion/nzgd1949-nzgd2000/distortion-grid/
 nzgd49  "nadgrids=nzgd2kgrid0005.gsb"  "New Zealand"   "LINZ NZGD49 NTv2 Distortion Model, accuracy 10-30cm" 
 # http://www.linz.govt.nz/geodetic/conversion-coordinates/geodetic-datum-conversion/nzgd1949-nzgd2000/three-and-seven-parameter/
+#  note: values in above URL use the Helmert convention for the sign of rotation terms, while PROJ.4 uses the Bursa-Wolf convention.
 nzgd49  "towgs84=59.47,-5.04,187.44,0.47,-0.1,1.024,-4.5993" "New Zealand" "Accuracy approx. 4m"
 tokyo   "towgs84=-147.54,507.26,680.47" "Japan" " "
 tokyo   "towgs84=-147,506,687" "South Korea" " "