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0

Choosing CC47 as layer CRS is wrong in most situations, because that has no influence on the coordinates of the layer. So put it back to Lambert 93. When you export to DXF, you can choose CC47 for that DXF, and all coordinates will be reprojected to that CRS.


-1

Try subtracting large portions from the oceans of your azimuthal equidistant model by condensing them into three equilateral triangles near the equator on faces which would be equidistant in a geospheric earth model, then designating the triangles "spooky anomalous no go zones" ingame to explain away the gps failings, hide easter eggs there or something.. ...


0

Besides GDAL/Fiona you can alternatively use PyCRS, a package written in pure Python specifically for defining and converting between and projection formats. So in your case: import pycrs wktstring = ...


2

The comment from @mkennedy revealed you may be missing one important part of your weighted average of Cartesian coordinates: 3780321.97159 -57867.5646271 5115866.05408 Converting these ECEF coordinates back to WGS84 actually produces an ellipsoid height parameter: 53.7184377538 -0.876990985207 -2971.299770 Notice the height is negative, and is actually ...


3

Set lon_0 to the middle of your study area. k can be set to 0.9996 (as UTM has). lat_0, x_0 and y_0 have no effect on the quality of the projection. They are usually set to the equator and/or the inverse of the lower left point so that all coordinates are positive.


0

I'll just post a few pointers here for now: when I get a chance, I'll try to make this a more comprehensive and easily-consumable answer. But for now: First off, consider changing your title better match (IIUC--ICBW) the terms folks in this domain use for this sort of usecase, and therefore to make it more findable. What you want to do is more usually ...


3

If you want to reproject data from one CRS to another, DO NOT simply change the CRS with Set CRS for Layer. This will NOT reproject any coordinates. So please change the CRS back to EPSG:4326 since that is the correct CRS for your lat/lon data. Instead, use Save As... to another file name and CRS. You might want to use ESRI Shapefile format, since CSV does ...


1

I was able to get the correct output by adding the following options to my gdalwarp command: -wo sample_grid=yes, -wo sample_steps=1000, -wo source_extra=2 -wo CUTLINE_ALL_TOUCHED=true -r cubic Thank you user30184 for pointing these out!


0

I changed boundaries of the layer to totally new numbers, other than on map and other than configured on GeoServer, this is the relevant code I added to Layer init: tileGrid: new ol.tilegrid.XYZ({ extent: [-380188, 5249943, 1347312, 8226943], resolutions: [2048.0, 1024.0, 361.0, 256.0, 128.0, 64.0, 32.0, 16.0, 8.0, 4.0, 2.0, ...


1

Ok, I've figured it out. It is possible to apply an affine transform onto some existing CRS using FITTED_CS. Below is an example of rotation of 60 degrees counterclockwise and movement: FITTED_CS["BPAF", PARAM_MT["Affine", PARAMETER["num_row", 3], PARAMETER["num_col", 3], PARAMETER["elt_0_0", -0.5], PARAMETER["elt_0_1", ...


2

I'm not sure what NOAA thinks are the right coordinates, but I have no problem loading the file into QGIS, or reprojecting it to WGS84 with gdalwarp: QGIS uses this custom projection string: +proj=lcc +lat_1=25 +lat_2=25 +lat_0=25 +lon_0=265 +x_0=0 +y_0=0 +a=6371229 +b=6371229 +units=m +no_defs You can use the same string with pyproj.Proj(). where you ...


1

You can define a local rotated coordinate sytem as I explained here: Using customized Coordinate System for Archaeological site data Center point and rotation have to be defined in degrees. Your idea of wrapping one projection with another is not defined in PROJ.4. You can try it out, but don't expect it to work.


1

@whuber's assertion that an equal-area projection "will give absolutely correct areas" comes with an asterisk, namely, assuming that the edges of the polygon are straight lines in said projection. This is often a good approximation, particularly if the edges are short; but it is rarely strictly true. If, on the other hand, the edges of your polygon are ...


7

"EPSG:3488, EPSG:NAD83(NSRS2007) / California Albers" is an equal-area projection. It is based on the Albers Conic, which is defined for the northern hemisphere. Because Sweden is within its range of definition, it is equal-area in Sweden. This means that (up to floating point rounding error) it will give absolutely correct areas. Neither the Mollweide ...


1

With a dynamic map service, you can simply request it in a different coordinate system using the spatialreference parameter. Lets assume you already have a map defined in your javascript app, with a spatial reference of 4326 (web mercator), by simply adding the dynamic map service, (with a differing supported spatial reference) it will automatically ...


3

The length of degree in north-south is about the same so you could use 1/110574 degree/meter as a factor. However, the farther to south or north you go the bigger the error is in east-west direction. For example, take these two shapes which have a 1 degree buffer in EPSG:4326 transformed into EPSG:32630 (UTM zone 30N). First one is from 40°N and the second ...


0

Here is the arcpy/python script flow: Use os.walk to iterate through directory and sub-directories Once shp is found use ListFields function to get a list of all shp field names Use condition if logic to check if field name exists in fc from ListFields list If field name does not exist use Add Field method to create the field Use Project method to ...


0

I found the solution using org2ogr library by using ogr2ogr -s_srs EPSG:2100 -t_srs EPSG:3035 outfile.shp infile.shp


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Got it: var vectorSource3; $("#city").keypress(function (e) { var code = (e.keyCode ? e.keyCode : e.which); if (code == 13) { //Enter keycode return false; } }); $(function () { function log(message) { $("<div/>").text(message).prependTo("#log"); $("#log").scrollTop(0); } ...


0

As a potential starting point for a list of differences it might help to see my new PyCRS package, where I have attempted to create a class for each crs element, parameter, and datum/ellips/proj name, along with their esri_wkt vs ogc_wkt spelling. I have also specified how I see the parsing differences in terms of the wkt structure as a whole in the ...


0

You can also use the Proj4 library. I think the number of supported projections is bigger than in all others. As far as I know the supported number of projections in NetTopologySuite is very limited. There is a wrapper available in order to use Proj4 in C#: http://ftp.dfg.ca.gov/Public/BDB/Tools/proj4/


2

As an approximation suitable for medium-small radii, use the cos() of the latitude to scale up the true distance to a "distance" that makes sense for your latitude in web mercator, as described here. SELECT * FROM mytable WHERE ST_DWithin( ST_Transform(ST_SetSRID(ST_MakePoint(%lon, %lat), 4326), 3857), the_geom_webmercator, %radius / cos(%lat * ...


1

Rightclick -> Saxe As ... to reproject a layer only works for vector layers. Raster layers are a bit more complicated, you have to use Raster -> Projections -> Warp(Reproject) with a new file name and source CRS different from target CRS.



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