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1

Georeferencing is a process where you define which coordinates your image covers. It'll write in the coordinate system of the data frame. Therefore, it does not specify which coordinate system you use, only which coordinates it covers. The tool Define projection (under Data Management --> Projections and transformations) can be used on both vector and ...


0

Maybe this is a different workaround than you are thinking, but when I have had issues with the Google Maps plugin I reprojected my data into EPSG:3857 and then did all my work there, then I reprojected it back to the original projection once I finished. I've also realised when working with the plugin that sometimes the projection renders a little wonky ...


3

To determine whether an arcpy SpatialReference object is projected or geographic use the property type: geoSR = arcpy.SpatialReference(4326) print geoSR.type Geographic projSR = arcpy.SpatialReference(28356) print projSR.type Projected


2

Every set of coordinates stored inside SDE.ST_GEOMETRY is stored as a compressed array of 8-byte long integers. The IEEE floating-point to integer conversion is performed by subtracting the coordinate reference X_OFFSET (or Y_OFFSET, or Z_OFFSET, or M_OFFSET) and multiplying by the XYUNITS (or Z_SCALE or M_SCALE). The process is reversed when querying for ...


4

Trying to find a solution, I've changed OpenLayers.js file, provided by plugin authors (which had 'Release 2.11' version in his body and was placed at ~/.qgis2/python/plugins/openlayers_plugin/weblayers/html folder in my system) to last 2.13.1 version from official OpenLayers site (pay attention, 2.+ version!). Just download the archive, extract to ...


0

WGS84 is a coordinate system, but it's a Geographic coordinate system, which means it's referenced to a sphere (or ellipsoid). Note that it's also a datum, so if the full name you see under the coordinate system properties is WGS84, that's GCS, but you may also see WGS84 as part of a coordinate system name. You want a Projected coordinate system, which is ...


0

Seems like the settings are not stored correctly. Here's the bug report for future reference http://hub.qgis.org/issues/11713


4

The geographic coordinates systems (also called lat/long) are defined by 3 features : a datum, a prime meridian (most of the time, it is Greenwich) and a unit (most of the time, it is degree). The EPSG code help to unambiguously identify a geographic coordinate sytem (you can find the description on spatial reference.org) GEOGCS["WGS 84", ...


1

You have to build the proj.4 string for the CRS from the parameters given: +proj=lcc +lat_1=44.883333 +lat_2=45.133333 +lat_0=44.791111 +lon_0=-93.383333 +x_0=152400.000000 +y_0=30480.000000 +a=6378418.9409999996 +b=6357033.3098455509 +towgs84=0,0,0,0,0,0,0 +units=us-ft +no_defs Note that x_0 and y_0 have to be in meters, while false Easting and Northing ...


3

You can have your WFS server reproject the data by adding the srsName parameter to your URL (i.e. http://ec2-54-69-8-151.us-west-2.compute.amazonaws.com:8080/geoserver/WRIA9/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=WRIA9:2009BuildingsCOS&maxFeatures=50&outputFormat=application/json&srsName=epsg:4326). Then your ...


0

Whenever you have to transform or convert data between two geographic coordinate reference systems (GeoCRS, also called datums), you may find that there are zero, one, or multiple possible transformations available. If there are multiple transformations, they usually differ by area of usage and/or accuracy. Some countries like Belgium have published ...


1

QGIS is not designed to handle J2000 data. Your data would have 4 coordinates (X,Y,Z and time), while QGIS only handles 2-dimensional coordinates (long and lat or X and Y). It is possible to reproject coordinates with cs2cs if you set the prime meridian according to the time. Every hour from 12 UTC is a shift of 15° to the greenwich meridian: put 7 51 in a ...


0

You should be fine if it was consistently undefined in them all but they all really had the same coordinate system (just not defined).


1

As per the response syntax and example in the documentation here, ArcGIS Server should definitely be returning the spatialReference to you explicitly. see this thread for more info about the confirmed bug.


1

Not sure by your question if you want the map spatial reference or a layer. For a map you may use the IMap.SpatialReference Property.


5

Assuming you have a reference to the feature class pFC: ERSI.ArcGIS.Geometry.ISpatialReference pSP = ((ESRI.ArcGIS.GeoDatabase.IGeoDataset)pFC).SpatialReference; coord=pSP.FactoryCode coord now contains the code for the coordinate system. Note that not all projected coordinate systems are defined in esriSRProjCSType, there are more constants ...


1

You would do something like this: dataset = "c:/data/landbase.gdb/Wetlands" spatial_ref = arcpy.Describe(dataset).spatialReference as per the ESRI help page here


2

The code looks like the USNG or MGRS coordinate system, see https://en.wikipedia.org/wiki/United_States_National_Grid and https://en.wikipedia.org/wiki/Military_grid_reference_system for further details. 12RVU indicates that you are in UTM zone 12, somehwere in Western Mexico. You might need to read the manual on how to change the setting (I don't have the ...


4

Based on the conversation on the comments, ArcGIS online is making a guess at the coordinate system, while ArcMap is not. When it encounters an unknown coordinate system, ArcGIS Online appears to automatically assume WGS 1984. ArcGIS for Desktop treats undefined coordinate systems differently and does not make assumptions about the data's actual coordinate ...


3

The spatial reference for a map is defined either by the extent passed to the map constructor or by the first layer added to the map. Checkout the any projection sample to see how to specify different spatial references for a map. If you're using the basemap or center and zoom options with the map constructor, the map's spatial reference will be web ...


0

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


3

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): ...


4

If you divide those "strange" latitudes and longitudes by 11930465, you get the North and East degree values you expect: But don't ask me why ;-)


3

You are probably looking for the Define Projection tool (under Data Management, Projections and Transformations). Unlike Project, which will transform from one coordinate system to another (e.g. -119.789° becomes some large number of meters), Define Projection changes the coordinate system for the data itself and is appropriate to use when ArcMap is ...


2

Taking the suggestion by mkennedy for EPSG:28992, the points are located this way: which does not fit well, unless the WGS84 coordinates are rough or wrong. There is also an Amersfoort RD Old projection, but that is far off. Looking closer, the RD New points perfectly match to adresses in Openstreetmap, while the WGS84 are just road junctions; the lower ...


3

I'd suggest not writing this yourself, but instead using one of the existing coordinate transform libraries, such as proj4j or the CRS part of GeoTools. From GeoTools (with some JTS help): import com.vividsolutions.jts.geom.Geometry; import org.geotools.geometry.jts.JTS; import org.geotools.referencing.CRS; import org.geotools.geojson.geom.GeometryJSON; ...


0

Use ERDAS Imagine Coordinate Tools.


0

So over the weekend I found that my coordinate system stays constant if I output the raster to a TIF instead of GRID. I don't know if I can work all the Spatial Analyst tools with a TIF as well, so will have to try and see which format works better for me... Thank you for your help! :)


0

You can download UTM border shapefiles from the official source http://earth-info.nga.mil/GandG/coordsys/grids/universal_grid_system.html. Compute the centroid of each zone (an easy task for every GIS software) and save the coordinates of the centroid points for further use.


0

You could try ESRI:102013 it is the Europe Equal Albers Area. Kind of like the USGS albers projection but for Europe. I would be concerned than Finland is on the geographic fringes and actually into the polar regions and this is better suited for mid-latitude Europe. An non-ESRI definition appears to exist. EPSG:3035.


0

You do not need any reverse engineering. ogr2ogr is able to read the projection information from prj file for you. Just execute: ogr2ogr -t_srs EPSG:4326 -f geoJSON -lco COORDINATE_PRECISION=7 future.geojson your_shapefile.shp


1

After many attempts and even contacting the man, Denis Carrière , who created the geocoder module on Python, please find the solution below. I feel a bit drained after providing this first foray into developement , although my script was different initially, but I feel happy with the results and the helps. :) All done in Python, of course. import ...


0

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.


2

As commented by @jbchurchill and @user23715, I recommend checking your Output Coordinates setting under your Environments tab to see what it is set to. I/we do this because in the Point To Raster (Conversion) help it lists the Environments respected by that tool as being: Environments Compression, Current Workspace, Output Coordinate System, ...


2

Yes, you may use this site for batch processing: Batch Conversions of Latitude/Longitude to Address (Reverse Geocoding) 46.7270,2.5059 = Rue des Varennes, Saint-Amand-Montrond, Cher, Centre, Metropolitan France, 18200, France This site uses MapQuest reverse geocode service. You will have to apply some additional logic to parse out the city/town name ...


1

What you need to do is a spatial join on the lat/long coordinates and the french postal zones Here is the tutorial http://www.qgistutorials.com/en/docs/performing_spatial_joins.html The GIS DATA... postal zones can be found on this website https://www.data.gouv.fr/en/datasets/correspondances-code-insee-code-postal-idf/ Hope this helps!!


3

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 ...


1

I declared one point in each octant of the globe, transformed it to XYZ using the equations I had, and then tested martin f's answer. It didn't returned the same points. Then I delved deeper into Wikipedia's equations, and I finally understood how they worked. Then I adapted them. latitude(r, x, y, z) = arcsin(z/r)(180/π) longitude(r, x, y, z) = if (x ...


2

If you need high accuracy distances, or "ground" distances, you need to convert your UTM "grid" distances (which you do indeed calculate via pythagorous) using a combined scale factor. This removes the distortion introduced by the combination of (a) reducing the horizontal distance at its elevated (above the ellipsoid) position on the earth and (b) ...


4

The best way I can think is to get two UTM points, convert them to Lat/Long, and compare their geodesic distances to their UTM pythagorean distance. E.g. Take a point from this example: The CN Tower is ... in UTM zone 17, and the grid position is 630084m east, 4833438m north. So if we take A (17n 630084 4833438) and move it 30 km east, we get B (17n ...


0

The wiki reference you cite is based on a mathematical, not a geographic/cartographic, convention, as you say. It does however try to relate the geographic/cartographic equivalents. Here's my interpretation of the equivalencies: Mathematics Geography/Cartography r, radial distance R + h, radius + altitude φ, polar angle 90 - φ, ...


1

We have set our Garmins to the Indian Thailand 1975 datum with Everest 1830 spheroid. Seems to match. Otherwise running WGS 84 gives us grids that are 3-5KM shy of true location.


0

As commented by @whuber: As ratios of two lengths, scales are inherently unit free. Some maps describe their scales as ratios of lengths in different units (such as feet or miles per inch)--and when they do, they are usually clear about what lengths are involved. In other words, the term "unit of measurement for scale" does not make sense to use. ...


1

Just a difference between documentation and code. Recent versions of Fiona sniff out whether there's an entry in the EPSG table corresponding to the projection and preferentially return that.


0

Not sure, it's better to use Fiona here. You can compare strings from your prj file for each layer using http://prj2epsg.org/search You can also try to use OGR from Python like below (except last line, it's an extraction from the Python GDAL/OGR Cookbook from osgeo import ogr, osr driver = ogr.GetDriverByName('ESRI Shapefile') dataset = ...


2

Your dataset should appear in QGIS with EPSG:5652. If not, use Set CRS for Layer to get it. The 6-digit CRS is EPSG:25832. Rightclick on the layer, Save As ... under a different name and that CRS, and add it to the canvas. It might be even enough if you just change the project CRS to EPSG:25832, leaving the dataset unchanged.


1

In your case you can add the item to define the crs string to the URI like &crs=EPSG:4326. Your code should look as follows: uri = "file:///C:/data.csv?type=csv&xField=lng&yField=lat&spatialIndex=no&subsetIndex=no&watchFile=no&crs=EPSG:4326" vlayer = QgsVectorLayer(uri, 'Points', "delimitedtext") ...


2

Can you try this (change GeoJSON to the format you want to load.): vector_format = new OpenLayers.Format.GeoJSON({ 'internalProjection': new OpenLayers.Projection("EPSG:31466"), 'externalProjection': new OpenLayers.Projection("EPSG:3857") }); result = vector_format.read(newFeatures); vectorLayer.addFeatures(result); This worked for me.


3

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 ...


0

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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