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The use of geographic vs projected is more up to you and your analysis needs. Based on what I've read so far in this question, it is not necessary for you to project into a UTM zone. However if you aren't consistent in picking the correct type of CRS, you will get alignment issues. Generally speaking (and there are exceptions) if your coordinate units are in ...


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NAD1983 is a geographic coordinate system. There are a few different ways you could go about aligning these data, but I'll give an example that I think is simple and clean. (1) Add both of your CSV tables to ArcMap and plot the points. Make sure you plot them using the correct geographic coordinate system - File1(NAD1927) and File2(NAD1983). Right click the ...


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In addition to AndreJ's answer, the gdalwarp command can be simplified as this: gdalwarp -s_srs EPSG:28193 -t_srs EPSG:4326 -of GS7BG in.grd out.grd No need to specify the entire proj.4 definition. On Linux systems this might work, as root: ln -s /usr/lib64/libproj.so.0 /usr/lib64/libproj.so


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For the first part of your question: GDAL can guess the format of the input file from the file extension. The output format is defined by the -f option. If it is missing, Geotiff is assumed, but you get that warning if the file extension is not .tif. For a .grd output, you can select between GS7BG (rw+v): Golden Software 7 Binary Grid (.grd) GSAG (rwv): ...


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Why can't you use the Field Calculator to recalculate the Lat/Long once you've done the data transformation? If you need to preserve the original values (for some reason), then add two new columns and calc those with the NAD83 values.


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The question's asker reported that he was able to answer this using arcpy.CreateCustomGeoTransformation_management converted to Python from ArcMap He followed advice in a GeoNet thread. If/when he or anyone else provides more details as an answer here, then I can delete this one.


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Your Gauss-Krueger projection uses +datum=potsdam. Up to 2012, this was hard coded in proj4 to a very unprecise value using a 3-parameter-transformation. You find more exact values for 7-parameter transformations in this topic: http://forum.openstreetmap.org/viewtopic.php?id=12723 There is an even better ntv2-grid transformation available here (take the ...


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You can't transform from one SRID to another without knowing what the SRID you are transforming from is. It looks like in your case that the coordinates are Spherical Mercator, which is SRID 3857. So, if this is true, then you can use ST_Transform in conjunction with ST_SetSRID: UPDATE roads SET geom = ST_Transform(ST_SetSRID(geom, 3857), 4326); and then ...


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Thats because effectively you say "the coordinate 698745.50201423 4210011.04002000 is in SRID 4326", which is not what you want. You want to transform the coordinate from your source reference system to a destination reference system. So you need to: Know the source coordinate system Use ST_Transform ( see http://postgis.org/docs/ST_Transform.html )


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If you have data from the poles, avoid EPSG:3857, because that is undefined at the poles. Reprojection might fail, and the rest of the data might get lost. Try EPSG:4326 instead. To get the full picture, include the target extent (for the Arctic region): gdalwarp -t_srs EPSG:4326 -te -180 -90 180 90 northpsg.20141027 output.tif and you will get your ice ...


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Two separate marker-transform properties can't be applied for the same object, but if you can apply a single property with multiple functions in it: marker-transform: 'scale(0.5) rotate(180)'; However this would likely require you rearrange your code to apply the correct rotations at the same time and make things more complicated. A simpler approach ...


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You may have swapped the coordinates somewhere. If I reproject your resulting lonlat coordinates 103.919768 1.125312 103.690059679 1.35650722603 I get with cs2cs using: cs2cs -f "%%.6f" +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs +to +proj=tmerc +lat_0=1.366666666666667 +lon_0=103.8333333333333 +k=1 +x_0=28001.642 +y_0=38744.572 +ellps=WGS84 ...



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