Questions tagged [epsg]
A group that maintains a freely available database with standard codes for coordinate systems, datums, spheroids, units and the like
471
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Difference between WGS84 and EPSG:4326
What is the difference between WGS84 and EPSG 4326?
It seems like for a given dataset it might be both WGS84 and EPSG:4326.
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What's the difference between EPSG:4326 and EPSG:900913?
I am a bit confused on EPSG:4326 and EPSG:900913. I thought that they were both same. Though as I am placing my features over GMaps, which is EPSG:4326, I need to define the srsname of the WFS layer ...
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What is the current Web Mercator projection code?
The web mercator projection, popularised by Google Maps, seems to be given a new EPSG code every couple of years.
EPSG:900913 (Google in calculator text) was an unofficial code
EPSG:3785 - is the ...
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What is the difference between EPSG:900913 and EPSG:3857?
I'm using the QGIS google layers plugin to digitize a parcel as a shapefile. Later I want to import it to PostGIS. I know that google maps use a special 'google mercator' projection. What is the ...
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Changing projection of shapefile in QGIS
How do I change the projection of my shapefile using QGIS?
The default projection is set to EPSG:3003, I want to change it to WGS84 EPSG:32632. When I do a reprojection or I change projection in the ...
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3
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Do ArcGIS SpatialReference object factory codes correspond with EPSG numbers?
I've got a project where I'm reading in geometry objects from text files to put them in ArcSDE. These geometry objects have an associated EPSG code, and I'm looking for a way to ensure they're in the ...
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Using customized Coordinate System in ArcGIS Desktop?
I don't know so much about coordinate systems...
In my office we use to deal with spatial data coming from archaeological sites. Each site has its own x-y-z coordinate system (GCS). Three simple ...
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Change OpenLayers 3 view center
I'm using OpenLayers 3 to interact with some maps. I first declare my map:
map = new ol.Map({
target: 'map',
layers: [
new ol.layer.Tile({
...
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3
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How can EPSG:3857 be in meters?
It is said that unit of measure for EPSG:3857 is the metre.
How it can be, if the range of these coordinates is
Projected bounds:
-20,026,376.39 -20,048,966.10
20,026,376.39 20,048,966.10
(from the ...
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3
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How to georeference a web mercator tile correctly using gdal?
As an example I will take the following tile http://a.tile.openstreetmap.org/3/4/2.png and save it as "4_2.png".
The WGS84 coordinates of this tile can be calculated or read there by ...
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Reprojecting WGS 1984 Web Mercator (EPSG:3857) in Python with GDAL
I am reprojecting rasters in python using GDAL. I need to project several tiffs from geographic WGS 84 coordinates to WGS 1984 Web Mercator (Auxiliary Sphere), in order to use them later in Openlayers ...
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1
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How do coordinate reference systems and projections relate to each other?
I would like to resolve some general confusion of mine concerning the terms (and concepts) of "coordinate reference system" and "projection". The way I initially understood these terms is that a CRS ...
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1
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Integrating NTv2-transformation in QGIS?
I am wondering what's the correct way to integrate a NTv2-transformation in QGIS.
I have successfully integrated a NTv2-transformation in QGIS but I am not sure if it's done the way it's meant to be.
...
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Why accurate area of all countries cannot be obtained using a single EPSG code, even if it corresponds to an equal-area projection?
I would like to check if using different equal-area projections lead to near-identical area estimation for a list of countries.
Importing modules:
import numpy as np
import geopandas as gpd
import ...
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Extracting EPSG from a raster using gdal bindings in Python [duplicate]
My goal is to check that a shapefile and raster have the same projection and datum using EPSG number.
One can easily extract EPSG number from a shapefile by the following:
ds=ogr.Open(r'.......
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What's the meaning of numbers before an EPSG code, e.g. the 6.9 in EPSG:6.9:4326?
A WFS server I was using offered boundaries data in the following EPSG codes:
EPSG:6.9:27700
EPSG:6.9:4326
...defined in the XML giveCapabilities spec like this:
<DefaultCRS>urn:ogc:def:crs:...
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2
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What is the difference between spatialreference.org catalogs: EPSG, ESRI, and User-defined?
I'm trying to understand EPSG codes. I've been to the spatialreference.org site, and in its "about" link, it states:
"There are currently three distinct catalogs of spatial reference systems on this ...
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Convert UTM zone into EPSG code
I have the UTM code 36S and want to convert it to EPSG.
Somebody told me that if the UTM code contains 'S', then the first three digits of the EPSG code are 327, and if the UTM code is 'N' then use ...
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How can I convert geomagnetic coordinates to geographic coordinates without doing the math myself?
I have some data which are in geomagnetic coordinates; that is, they are latitude and longitude, but in reference to the magnetic north pole in Canada rather than the geographic north pole. As you ...
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What is the proj4string of the Lambert azimuthal equal-area projection?
Shapefiles of European data are available on the Eurostat website. I have loaded the NUTS_2013_60M_SH Shapefile in R with the command;
europeRG <- readOGR(dsn = patheurope, layer = "...
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1
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Why isn't QGIS detecting CRS from .prj file?
I have a number of 1 km hexagonal grids that cover various counties in the United States in a postgreSQL/postGIS database. Each grid has the CRS EPSG:3857, and the counties layer has EPSG:3857. When ...
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Using Fiona to write a new shapefile from scratch
I am new to Fiona, and trying to wrap my head around reading a csv file and writing out an ESRI shapefile. I have most of it down, but am missing two things; (1) defining the projection/spatial ...
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2
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Finding out whether an EPSG code is geographic or projected in Python
Can one tell that from the number of digits or a similar rule?
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1
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QGIS and Mapinfo reporting different projections for some files
When I open a tab file that's been generated in QGIS using EPSG 28355 (MGA 94, z55s) using QGIS 3.10 the projection is transformed to 5551
But when I open it in Mapinfo v17 it's correctly reported as ...
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What is the SRID for EPSG 102743?
I am trying to create a table in PostGIS for some LiDAR data and I need to set the the_geom column to my data's SRID. My data is in EPSG 102743, but when I try to use 102743 as my SRID as the_geom I ...
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How to find the extent of (many) EPSG CRSes?
I want to map the geographic extents / bounding boxes of a lot of EPSG CRSes. At least, those with a rectangular geographic extent.
For example, take epsg:2004, visiting that page shows the extent (...
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Is there a standard vertical datum for meters below the WGS84 ellipsoid, or below MSL?
I have data I am publishing a WMS layer representing data under the surface of the water, say temperature at 100m depth. What is the accepted way to represent this in WMS GetCapabilities document?
...
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Convert GPS coordinates into 3-dimensional cartesian coordinates (x,y,z)
In a nutshell:
What is a valid EPSG code for an earth fixed 3-dimensional cartesian coordinate system?
If it is 6500: How can I trick the python library pyproj into using this 3D coordinate system ...
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How do I convert to EPSG:3857 with GDAL?
I have some TIFs in EPSG4326 the GeoTiff info looks like:
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
...
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Converting EPSG:2284 to EPSG:4326 with pyproj
I have some points in EPSG:2284 and I'm trying to convert them to EPSG:4326 using pyproj, however I get weird results. When I go to the spatial reference website
I see that there is an endpoint that ...
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Order of latitude and longitude in EPSG:4326
I recently started working with GPS data in PostGIS and am very confused about the order of latitude and longitude. I'm from Europe, and here everyone I know uses latitude first, longitude second, e.g....
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Google Earth Engine Reprojection to non-EPSG defined CRS
Is it possible to reproject an image in earth engine to non-EPSG defined coordinates? In particular either Goode Homosline (SR-ORG:7619) or Mollweide (ESRI:54009). Passing either to .reproject() ...
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Is there an EPSG code to specify WGS84 in (lon,lat) order instead of (lat,lon)?
Is there an EPSG code like EPSG:4326 or EPSG:4329, but that specifies (lon,lat) order instead of (lat,lon)?
I've tried exploring the websites
http://spatialreference.org and
http://epsg-registry....
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Are these two OGC WKT projections the same? And if so, why are their reference strings different?
So here is the .prj text of a federal shapefile dataset of all public airports in its native OGC WKT format:
GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],...
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Understanding EPSG in WKT
I notice several EPSG codes in one WKT. At the first glance it almost is non-intuitive to see so many EPSG codes linked to a single EPSG.
Can someone explain each line of the following WKTs for EPSG:...
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Where do I find CRS axis names?
When using the SUBSETTINGCRS argument of a WCS query, one needs to provide the axis labels in the subsetting CRS.
This answer to GeoServer does not work WCS parameters "subsettingcrs" and &...
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1
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How to choose the EPSG projection?
Up until now for reprojection of my WGS84 vector (.shp) and raster files (.tif), I have been using EPSG projections based on vector/raster central point's UTM zone.
But what happens if the envelope-...
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Distances in {Plate Carrée projection - EPSG:4326 - WGS84}
"4326 is just the EPSG identifier of WGS84" [3]
Indeed http://spatialreference.org/ref/epsg/4326/html/ says it is a GEOGraphic Coordinate System:
GEOGCS["WGS 84",
DATUM["WGS_1984",
...
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How do I change an existing srs in QGis?
I am showing postgis data with srid 28992 (Amersfoort / RD New). But when I plot the geospatial data on a map (with openlayers plugin), the data is shown a hunderd meters off because the datum shift ...
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proj4js with geocentric CRS
I am developing a little web app to transform coordinates between CRSs. To do that I am using proj4js, but I notice that proj4js can't work with geocentric CRSs.
Is there another tool similar to ...
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Listing all EPSG projections to serve it on the client side
I am building a web app that allows user to convert and reproject their spatial data and then download it. I am using Flask and ogr2ogr to achieve this.
Now, I want to give users a list of EPSG ...
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Coordinate system for Finland in ArcGIS Desktop?
I have a shapefile of Finland in WGS84 (EPSG:4326), that I would like to convert to projected coordinate system, most commonly used in Finland.
But, here is my confusion:
I have found that from ...
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PROJ.4 How to create custom CRS to displace by x and y?
I'm trying to create a custom CRS with proj4. I need to displace coordinates by adding 10 meters east and 20 meters north from EPSG:32719.
How can I do that with PROJ.4?
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leaflet map crs is 3857 but coordinates 4326
I am developing my first leaflet applications. So this is my trial application demo.
var osmUrl = 'http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',
osm = L.tileLayer(osmUrl, {
...
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How to fix distortions in rendered OpenStreetMap maps?
I use OpenStreetMap in order to generate maps and add some cool stuff in it. Actually I have good results but I seem to have a problem with reporting a good image ratio when I create my generated file....
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How to transform EPSG:3857 to tile pixel coordinates at zoom factor 0?
I'm creating a Leaflet map with an WebGL overlay (using L.CanvasOverlay) which renders a street network on the GPU.
Let's assume I have a point (1497143.62, 6896952.18) in EPSG:3857 and want to ...
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Converting EPSG to D3.js
Given an EPSG projection (say, this Alabama one: http://spatialreference.org/ref/epsg/26729/)
How can you take the given WGS84 projection bounds in such a way that you can use them in a D3.js ...
6
votes
1
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Definitive list of Proj4 supported coordinate systems
I need to determine the minimum set of coordinate systems supported by all tiers of my project's stack. I have a list of EPSG codes supported by Oracle and GeoServer but I'm having trouble finding a ...
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Is there an alternative to prj2epsg.org?
In the past, we used prj2espg.org to find the srid/espg code from .prj file of shapefiles in order to import them in PostgreSQL.
Unfortunately, the website seems to be down since November 2019 (...
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PostGIS spatial reference ID (SRID) for regular cartesian coordinate system?
I would like to store a polygon as a set of 2D points represented as x, y coordinates of a Cartesian coordinate system.
Which spatial reference can I use? Looking at my spatial_ref_sys table, all the ...
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