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6

Short answer is yes. You need to convert from your coordinates' native reference frame to the NAD83 realization's reference frame, then possibly add an adjustment. In the case of NAD83(CSRS), which I use, there are 3 steps: Native RF -> ITRF96(1997.0) ITRF96 (1997.0) -> NAD83(CSRS) Grid shift Steps 1 and 2 require the Helmert transformation. Step 3 uses ...


4

When you read the CSV file into a Qgis layer, you can iterate over the features and apply some processing like this: # path to CSV file filename = 'e:/gps2geometry.csv' # connection string for CSV file reader, \t: separated by tabs uri = 'file:///%s?crs=%s&delimiter=%s&xField=%s&yField=%s&decimal=%s' % (filename, 'EPSG:4326', '\t', 'X', ...


3

You can copy the gps data to an excel-file (or any othe similar program). It will look samething like this: ID A B 1 Lat Long 2 50.123 7.123 3 50.321 7.321 If it only contains the lat/long in one column ("51.123N7.123E") you have to devide that value to two columns. Than you insert a new column C with the header "wkt" (=well known text) and in ...


2

The *.osm file is a *.xml file. There is no need to convert it. Open the file within an editor of your choice and you will see the xml structure. If your application needs a file with *.xml ending simply rename it or use the *.osm file as an input. Both should be fine.


2

Oh well, answering my own question again; hoping someone else finds it useful! Using Windows Powershell, the below. Place the source images (jpeg image files in my example) in directory foo, the create the outputdir directory. Then execute this command: dir -recurse -include *.jpeg | %{convert $._FullName -crop 50x50@ +repage +adjoin ...


2

If you have TransCAD, you can use the Caliper Python module that lets you access TransCAD and it's programming language GISDK via a program written in Python. With it, you can write a Python program like the one below: import sys, traceback, caliper dk = caliper.Gisdk("TransCAD") rh = dk.GetFirstRecord(view_set) for row in ...


1

There is a good explanation at the OSM wiki. It boils down to projecting EPSG:4326 coordinates to EPSG:3857 and working the X and Y coordinates of the tile from the X and Y coordinates in that CRS. The "generalized" way to provide tiles for any CRS is TMS.


1

You cannot convert raster to AutoCAD DXF/DWG. If you have georeferenced raster (e.g. GeoTiff) and AutoCAD Map, you can simply add the raster to your AutoCAD drawing. Vector features can be exported to DXF from QGIS and GRASS, too. In QGIS you can use Save as from the popup menu of the layer or Project/DXF Export from the main menu. In GRASS use v.out.dxf ...


1

If you use QGIS, download the plug-in named MMQGIS. There's is an option to Google Maps KML export. It is quite simple.



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