From 27c197f9da8005a2fd58bb8d902beb0864a2916b Mon Sep 17 00:00:00 2001 From: Frank Warmerdam Date: Mon, 9 Dec 2002 16:01:02 +0000 Subject: added prime meridian support git-svn-id: http://svn.osgeo.org/metacrs/proj/trunk@1041 4e78687f-474d-0410-85f9-8d5e500ac6b2 --- html/gen_parms.html | 43 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 42 insertions(+), 1 deletion(-) (limited to 'html') diff --git a/html/gen_parms.html b/html/gen_parms.html index 045eecf6..bc59b116 100644 --- a/html/gen_parms.html +++ b/html/gen_parms.html @@ -1,4 +1,4 @@ - +w PROJ.4 - General Parameters @@ -20,6 +20,47 @@ Virtually all coordinate systems allow for the presence of a false easting meters even if the coordinate system is some other units. Some coordinate systems (such as UTM) have implicit false easting and northing values.

+

pm - Prime Meridian

+ +A prime meridian may be declared indicating the offset between the prime +meridian of the declared coordinate system and that of greenwich. A prime +meridian is clared using the "pm" parameter, and may be assigned a symbolic +name, or the longitude of the alternative prime meridian relative to +greenwich.

+ +Currently prime meridian declarations are only utilized by the +pj_transform() API call, not the pj_inv() and pj_fwd() calls. Consequently +the user utility cs2cs does honour prime meridians but the proj +user utility ignores them.

+ +The following predeclared prime meridian names are supported. These +can be listed using the cs2cs argument -lm.

+

+   greenwich 0dE                           
+      lisbon 9d07'54.862"W                 
+       paris 2d20'14.025"E                 
+      bogota 74d04'51.3"E                  
+      madrid 3d41'16.48"W                  
+        rome 12d27'8.4"E                   
+        bern 7d26'22.5"E                   
+     jakarta 106d48'27.79"E                
+       ferro 17d40'W                       
+    brussels 4d22'4.71"E                   
+   stockholm 18d3'29.8"E                   
+      athens 23d42'58.815"E                
+        oslo 10d43'22.5"E                  
+
+ +Example of use. The location long=0, lat=0 in the greenwich based +lat/long coordinates is translated to lat/long coordinates with Madrid +as the prime meridian.

+ +

+ cs2cs +proj=latlong +datum=WGS84 +to +proj=latlong +datum=WGS84 +pm=madrid
+0 0                           (input)
+3d41'16.48"E    0dN 0.000     (output)
+
+

towgs84 - Datum transformation to WGS84

Datum shifts can be approximated by 3 parameter spatial translations (in -- cgit v1.2.3