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I have had difficulties importing XY data to a specific projection. I don't recall ever crashing from attempting this, but weird things have happened. Assuming your x and y columns are in or have been converted to decimal degrees, here is what works reliably for me in Arc 10.2: -Open a blank MXD and define the Coordinate System as (Geographic): ...


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I have constructed below a well-known text (WKT) file for the projected coordinate system that your data is using. You should copy it to a text file that has an extension ".prj". The WKT string must be a single line. Put the text file into your ArcGIS installation folder, then "Coordinate Systems, Projected Coordinate Systems". When you want to project your ...


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I believe what you are experiencing is more or less a copy of this question. The coordinates in the rainfall data are in longitude/latitude, but with values ranging from 0 to 360, instead of -180 to 180 (as your political boundaries are). See the GPCC spatial note here (emphasis mine): Spatial Coverage: 0.5 degree latitude x 0.5 degree ...


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The Mercator projection, is a conformal map projection so any angles measured on the map are the same as if measured on the globe. It also has the property that all straight lines on the map represent loxodromes, or lines of constant azimuth. Those are useful properties in surveying and navigation. Beyond that, however -- and especially when mapping very ...


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Orthographic projection is able to show the poles, which mercator can not do. Furthermore, the projection looks like the view from outer space, which feels kind of natural. It only shows half of the worlds surface, but that's what you see from outer space. An even more "natural" view would have resulted from a perspective projection, which looks like the ...


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Web Mercator has only real metres as units close to the equator. The more to the poles you come, the more x and y distances get apart. You should better use a "good" projection like the UTM zone of your area if you want to see the lines in correct length.


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Your problem is that WFS 1.0.0 does not support reprojection of the coordinates. If you switch your request version to 1.1.0 then GeoServer will take your srs into account.


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I defined the srid wrong. Transposed the 8 in 3857 for the 5. I used the statement below to fix!!!! Forest for the trees! SELECT UpdateGeometrySRID('roads','geom',3857);


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The error is not on your side, but on Google's side. See http://alastaira.wordpress.com/2011/01/23/the-google-maps-bing-maps-spherical-mercator-projection/ http://www.hydrometronics.com/downloads/Web%20Mercator%20-%20Non-Conformal,%20Non-Mercator%20(notes).pdf They claim to use a sphere (a=b), but really use the WGS84 ellipsoid (a>b) lat/lon coordinates. ...


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The coordinate systems you mentioned, WGS 1984 and WGS84 Web Mercator (Auxiliary Sphere) (EPSG:3857), use the same spheroid and datum with parameters you written for WGS84. The semiminor and semimajor axis are not the same. Maybe that is the source of the error. See the description of the EPSG:3857 spatial reference.


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You'll need to define both a horizontal coordinate system (could be projected, like UTM) and a vertical coordinate system (like NAVD88, making sure to be in the same units as your horizontal). A vertical coordinate system expresses elevations relative to a baseline, usually a mathematical representation of the Earth's surface. Your measured elevations ...


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I have encountered your problem previously and I managed to fix it using this method which I hope works for you too. I added my file to ArcMap and, while the overlap is fine, I exported each layer, and in the export dialog I selected Use Same Coordinate System as the Data Frame. I then added the exported layers again to GeoServer.


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Yes, as whuber says, the gnomonic projection is the way to go. GeographicLib (written by me) includes an ellipsoidal generalization of this projection in which geodesics are very nearly staight. For example, if you consider two points 4000 km apart, the straight line connecting them in the gnomonic projection deviates from the geodesic by less than 30 m. ...


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Do the computations using the Cartesian formulas in a Gnomonic projection. These projections cover a single hemisphere and map all portions of great circles to line segments. Presumably, in the representation of your spherical polygons as sequences of (lon,lat) values it is implicit that each successive pair of vertices is to be traveled along a geodesic. ...


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Given your examples above, you must be using "Nearest Neighbour" option to do the resampling in the Project Raster tool. That's why some values "disappear". What else can it do, it takes the nearest value (measured by cell center position) and assigns it to the new cell in the new coord sys. A histogram of the cell values between the old & new can never ...


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Possible options: .prj file Create a .prj file which contains the EPSG:4326 that GeoServer does recognise. You can get this from the Demos -> SRS List admin page. Name this .prj file the same as your shapefile and if necessary overwrite the one that exists. Force declared When adding the layer, set the "Declared SRS to 4326" and the SRS Handling to ...


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If you are typing a geometry's WKT into pgAdmin III, you need to specify the SRID using EWKT syntax, otherwise it defaults to 0. Type this into the geometry field of pgAdmin III: SRID=26191;POINT(25800 256000) Otherwise, @MakinFlippyFloppy has the correct SQL way, using ST_SetSRID.


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Because you are "near" the equator, the cylindrical projections (like Mercator) work well (not too many distortions). If you want to be perfectly fair in terms of areas, you could use cylindrical equal area or sinusoidal projection. But this would not markedly differ from Mercator.


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What's happening is that the data you are trying to insert does not have an SRID assigned. To assign one, try wrapping the inserted geometry in your insert statement with ST_SetSRID(). E.g., INSERT INTO public.borne (num_borne, shape_borne) (SELECT num_borne, ST_SetSRID(shape_borne, 26191) FROM public.sometable); or INSERT INTO public.borne ...


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I thin below link can help you, Check out below page :: http://postgis.org/docs/UpdateGeometrySRID.html


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If you think of accuracy of distance measurement, mercator or transverse mercator with lat_0 and lon_0 set to the center of your area will do fine. Mercator has true lengths along the latitude, while transverse mercator has them along the meridian. So it depends on the format of your area which one is better. You can use omerc if you need a rotated grid.


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When you say that you have imported your CAD drawings into ArcGIS, I am assuming that you now have either file geodatabase feature classes or shapefiles. Consequently you should be able to perform a spatial adjustment transformation on them: Transformations move or shift data within a coordinate system. They are often used to convert data from unknown ...


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The problems arise because the CostDistance calculations use the (Euclidean) distance in a map as a surrogate for the true distances experienced on the globe's surface. This surrogate will be distorted in two ways: The relationship between map distance and globe distance will vary according to location on the map. At any given point, the map-globe ...


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Equidistant projections are not equidistant from all locations to all locations. As Vince states, if all your origins are (close to) centered on one location you can use the "equidistant" projection below and center it on your origin. If not then stick with the equal Albers Area USA. A would do test run in both. You can use ...


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Thanks for the solution. I was thinking of manipulating OSM.XML file to change the projection information and get a reprojected map on-the-fly. For example, I followed this tutorial but could not get the result. Just wondering if you have any experience in this regard. UPDATE: To have a map with a custom projection (rather than OSM default EPSG:3857), you ...


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I think you need to specify the srs parameter of your layer: srs : '32024' //NAD27 or srs : '32126' //NAD83


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Why not just use the gmap() functionality offered by the dismo package instead of ggmap? You can download Google maps of type 'satellite', 'terrain', 'roadmap' and 'hybrid' there as well. The advantage is that the thus aquired maps are instantly available as objects of class 'RasterLayer' or 'RasterStack', holding a defined spatial information. Setting ...


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This set of extracts from OSM data may be what you're looking for. In particular, this shapefile of the coastline around Helsinki.


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I wouldn't recommend to alter the projection already at the DB level, as a lot of tools rely on the default projection for OSM: Instead try to use e.g. Mapproxy to reproject the output tiles.


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If you want to measure in meters, switch the project CRS to a projection that uses metres, like the UTM zone of your part of the world. The layers can remain in the original CRS (something that SAGA presumably does not offer).


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You should be able to go into "project proprties/general" and check that "Canvas units (CRS transformation: ON/OFF)" is set to meters


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Two common cases: If you created the shapefile you will have to use the Define Projection tool to define the projection/coordinate system. If you downloaded the shapefile: Shapefile has spatial reference (nothing technically you have to do here, should load and re-project on the fly in ArcMap) Shapefile is projected, but no set spatial reference (look ...



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