Questions tagged [proj]
A library for performing conversions between cartographic projections.
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Pyproj Azimuthal Equidistant (AEQD) transformation always gives a small rotation as compared to country-specific CRS transformations
I am calculating building polygons from a satellite image.
This works accurately when using a country-specific CRS.
I would like to use a customer CRS, specific to the location at hand, but find that ...
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How to interpret inputs to General Oblique Transformation in proj?
I am trying to use the General Oblique Transformation to create a projection that is a rotated Oblique Mercator ... but I cannot for the life of me figure out what on earth that thing is doing.
I ...
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How to define a local projection with correct altitude for correct area-metrics
Using PROJ, and defining custom projection, by its PROJ-strings.
How to correct WGS84 altitude, to my "fit to local" reference?
For example this Albers projection for Brazil:
+proj=aea +...
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About CRS and map origin setting, What is their relation and math equation in leaflet.js via using proj4leaflet.js
I meet a problem about CRS function and map origin setting in leaflet.
I use proj4leaflet.js as the basic CRS function, and then after setting the origin of crs and
resolution, I can get the correct ...
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gdaltransform Cartesian transform change 2.2.0 to 3.4.1 proj.4 to?
Here are my results with 2.2.0 and 3.4.1. Can someone explain why this has changed?
echo -e "6720419.518191041 1878355.8391366536 1387.976960406033" | \
gdaltransform \
-s_srs "+...
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I am getting wrong north and east values after cartographic projection using PROJ library in C++
I am getting incorrect north and east values after cartographic projection from global WGS84 crs(i.e., EPSG:4326) to CRS Korean 1985/West Belt using PROJ C++ library. I got an error of approx. 1.5 cm ...
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Creating local coordinate system in QGIS
I am trying to create my own coordinate system in QGIS. My local system is defined as: base is Sweref 99 20 15 and then Helmert transformation with these parameters:
// Local transformation
...
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2
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Is there a way in PyQGIS to bypass the identify functionnality of QgsCoordinateReferenceSystem creation?
While implementing a geodetic buffering system similar to Approximating Geodesic Buffers with PyQGIS I noticed the buffering is extremely slow.
with Timer.context(msg="buffered_geom_function"...
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OpenLayers PROJ4JS projection of OSM layer is slightly translated?
I am new to OpenLayers and haven't been able to figure out this problem by searching online. I am using a custom projection in OpenLayers 7.4.0 with proj4 2.9.0 as demonstrated in this example. The ...
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Axes labels/names of QgsCoordinateReferenceSystem
Consider the following CRS as examples:
QgsCoordinateReferenceSystem.fromEpsgId(4326)
QgsCoordinateReferenceSystem.fromEpsgId(25832)
QgsCoordinateReferenceSystem.fromEpsgId(3857)
...
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Problems recovering 3d mesh from GeoTIFFs created from PDS IMG/LBL files using gdal_translate
Update:
I've discovered that the problem lies in the pixel scale. For example, when I use
`gdalinfo LDEM_512_90S_45S_000_090.tif`
it shows the following for the pixel scale values:
Pixel Size = (59....
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2
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70
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OpenLayers 7 WFS 1.1.0 not drawing polygons when srsName contains opengis.net/gml/srs/epsg.xml
I'm writing a web app that uses WFS data on top of OpenLayers with OpenStreetMap. The entire project works in EPSG:2180 projection and uses multiple versions of WFS (depending on server). OL doesn't ...
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How to convert point in any CRS to cartesian XYZ given the proj4 string?
I have GeoTIFFs of other celestial bodies, such as the moon, and am writing a program in C/C++. I cannot use GDAL but I can use libgeotiff, libtiff, and proj. Some GeoTIFFs are in a polar ...
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Generating 3d points from GeoTIFF using libgeotiff and proj
I'm working on a C++ library where I need to ingest several different DEM formats (such as GeoTIFFs, SPC Maplets, and some other internal formats) and convert them to a 3d triangular mesh. In the ...
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QGIS 3.22 support for topocentric CRS
I simply try to convert a point from local Cartesian ENU centered on a point with lat,lon coordinates to geocentric ECEF coordinates.
With proj from command line all works well.
I use strings from ...
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104
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Projection is not found when importing PostgreSQL file with Geopandas
I need to import a couple of files from my PostgreSQL database, which has columns with the geometrical data stored in the CRS "epsg:1330". There are no problems with opening the files using ...
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115
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Reprojecting NetCDF file from LCC to WGS84: 'Multiple grid mappings exist' error
I try to reproject a NetCDF file to WGS84 so I can clip it with a regional geometry for analysis. The file is a dataset with the CORDEX precipitation variable, climate change scenario rcp 2.6, years ...
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2
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Using NTv2 gridfiles in QGIS >= 3.22.x LTR with proj 9.x
This question is a follow-up to QGIS transformation defined in srs.db tbl_datum_transform table not available in Select Datum Transformations dialog
Basically it is all about making an NTv2 gridfile (*...
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204
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How do I use a .gtx file in pyproj?
I want to use the egm08_25.gtx file to convert from ellipsoidal height above goid.
from pyproj.transformer import TransformerGroup
t = TransformerGroup('EPSG:4979',"+proj=longlat +datum=WGS84 +...
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How to convert wgs84 from ellipsoidal height to mean sea level i.e. height above goid, with pyproj?
I want to convert wgs84 coordinates with ellipsoidal height to wgs84 coordinates with height above goid. Therefore I have set up a new conda environment and installed pyproj, proj_data, see conda list ...
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Why are x and y switched here?
I'm trying to convert between EPSG:7665 and EPSG:32145, but I have to swap the x and y values to get the correct answer.
From this datasheet reference point, here's the position:
OD1097* NAD 83(2011) ...
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86
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PROJ Helmert temporal ETRF2000 to ITRF2014
Just installed PROJ (Rel. 8.2.1) and GDAL (3.4.3), so apologies for my newbie questions as not found many examples of time based transformations. I have a FILE with the following coordinates in ...
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70
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GeoDjango: PROJ_DB version mismatch
PROJ and GDAL are having it out on my system; GeoDjango reports the following error message :
GDAL_ERROR 1: b'PROJ: proj_create_from_database: C:\\Program Files\\PostgreSQL\\14\\share\\contrib\\...
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145
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Query UTM grid for elevation at specific lat/lon coordinates
I need to query UTM grid data (25 meters) for elevation at specific coordinates in lat/lon form.
The UTM data uses the following proj parameters: +proj=utm +zone=32 +datum=WGS84 +units=m +no_defs.
I ...
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1
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173
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Incorrect coordinate conversion results from ProjNET when converting across horizontal datums
Been fighting this for almost a week now, so I'm hoping that someone here has some insight or can tell me the obvious thing I'm missing. I am trying to add programmatic coordinate conversion on the ...
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British National Grid shapefile prj subtle differences change polygon accuracy
I'll preface this question with the statement I know very little about projection systems so this is coming from a position of total ignorance.
I have two shapefiles. One is in England and one is in ...
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114
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Error in projNET and DotSpatial projection to EPSG:2950 coordinates
I need to convert a point from EPSG:4326 to EPSG:2950. But I am consistently getting a wrong result.
On the platform I’m using I can only use the following libraries:
projNET (link)
DotSpatial (link)
...
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381
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Transforming point from EPSG:3844 to EPSG:3857 with proj4js
I'm having an issue transforming a point from EPSG:3844 to EPSG:3857 using Proj4JS. The transformation it performs seems off compared to the result given by PostGIS, pyproj, rgeo-proj4 or even epsg.io....
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391
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Correct parameters to visualize WMS layers in Leaflet and proj4?
I'm struggling to visualize WMS-layers from a REST service using Leaflet. All I see currently is a gray map, not changing anything when moved.
The layers I want to visualize are located in Faroe ...
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Are there any limitations on the functionality of PostGIS related to the version of PROJ?
PROJ >= 7 optionally requires curl and libtiff. Are there any limitations on functionality of PostGIS if PROJ is not installed with them which are optional?
I would like to use all functionality of ...
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User Select CRS Tool
I am trying to create a tool which lets the user select a Coordinate Reference System from a list to project their data to. Are there any available libraries (preferably JS), datasets, or API's which ...
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Issue with swapped axes using projinfo/gdaltransform
I'm attempting to perform a coordinate transform operation using gdaltransform (version 3.6.0). Because of the possibility of different transform candidates when the transform involves a change in ...
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ST_Transform in PostGIS not working on Linux, GDAL 3.5.1, but working on MacOS, GDAL 3.5.3
I have a raster in PostGIS that has a non-standard projection, namely
select srid,proj4text from spatial_ref_sys where srid=9822;
srid | proj4text ...
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1
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156
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Cannot find OSTN15_NTv2_OSGBtoETRS.gsb
I'm running Proj 6.3.1
When running
projinfo -s epsg:27700 -t epsg:4326
Is see
Grid OSTN15_NTv2_OSGBtoETRS.gsb needed but not found on the system. Can be obtained from the proj-datumgrid-europe ...
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1
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252
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Pyproj transformation of a geopandas does not match QGIS reprojection
I have a file in British National Grid coordinates (EPSG 27700) which I'm trying to convert to WGS84 (EPSG 4326)
My first attempt was to transform in the usual way
import geopandas as gpd
file = '...
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62
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Arbitrary spatial rotation (Euler/Quaternion) using Proj transformation
I’m a geologist who is working with paleogeographic reconstructions (see example here). These require composite reproductions where different parts of a feature dataset (continents) are rotated with ...
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2
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886
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QGIS Error between EPSG and custom SRC
This is an error I get since the day I changed to 2.x to 3.x version.
Today, I am trying to fix it. I had QGIS 3.10 on Linux Mint from the repositories.
Then, I have uninstalled all, and I have ...
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207
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Shapefile Exported With CRS But CRS Unknown When Layer Added to New Project QGIS 3.22
I'm using QGIS 3.22. After right clicking and saving a defined CRS shapefile I open the layer in a new project, but the CRS is unknown. I thought that the Save Vector Layer as function permanently ...
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Combining affine transformations and COMPOUNDCRS
I have a need to define a WKT CRS which is both affine-transformed in 2D, and vertically shifted in the height direction. What I would like to say is something like this:
COMPOUNDCRS["Modified ...
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Which temporary projection is most suitable for calculating a buffer around a route
To create a buffer around route (for purpose of querying around a route), I figured I need to:
convert route points from geographic to planar coordinates
calculate a buffer
convert result back to ...
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Reproducing SWEREF99 to ITRF2014 Transformation using proj.org cct
The Swedish Geodetic Agency Lantmateriet provides a document (see references) with a procedure for transforming coordinates between ITRF2014 and SWEREF99. The document also provides and example of the ...
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219
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PDAL +init use deprecated but what is the alternative
With PDAL I was trying to using a proj4 string like +init=epsg:32615 +geoidgrids=C:\vdatum_GEOID12A\vdatum\core\geoid12a\g2012au7.gtx based on an example given on the PDAL website https://pdal.io/en/...
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Transform latitude and longitude to Transverse Mercator
I would like to transform point in WGS84 lat lon to Transverse Mercator:
+proj=tmerc +lat_0=0 +lon_0=114 +k=1 +x_0=-49099.65399999998 +y_0=-2544749.4072 +ellps=WGS84 +units=m +no_defs
I could easily ...
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59
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Proj R_A discrepancy with computed authalic radius
Using Pyproj, I attempted to create a spherical CRS using the authalic radius from WGS84:
import pyproj
wgs84_spherical = pyproj.CRS.from_proj4('+proj=latlon +ellps=sphere +R_A=WGS84')
print(...
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409
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Vertical grid shift with PROJ 9
I want to perform a vertical grid shift using PROJ 9.I have never used PROJ syntax and I am having some issues to have it right.
I have checked documentation and this previous post from which I got a ...
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59
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GDALWarp Reprojecting raster extent from (0, 360) to (-180, 180) filling left hemisphere with blank data
Understanding that this question has been asked a few times (Reprojecting raster from 0 360 to -180 180 with cutting 180 meridian using gdalwarp seems to be the canonical one), I've found that any ...
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60
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How to get CS2CS to recognize a 7-parameter Helmert shift (the +towgs parameter)
I have defined a transformation from WGS84 to ETRS89 Poland CS92 (Epoch 2019.5) in CS2CS.
I can do the basic map projection, but the datum shift is being ignored. It doesn't matter what numbers I type ...
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What is a source of Proj projections definitions?
I'm trying to create my own implementation of most popular projections (for reasons unrelated with GIS). But I want my implementation to be as compatible with Proj as possible (because it is an ...
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0
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155
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ST_TRANSFORM NAD27 to WGS84
I've encountered an issue when transforming NAD27 coordinates to WGS84. The resulting WGS84 coordinates are off by quite a bit (10-12 feet in most cases) and it lead me to digging into why that is so. ...
2
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1
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123
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gdalwarp to change my raster extents
I'm trying the gdalwrap command to set center and change the extent to -180 to 180. But for some reason, the bounding value is set but the pixel values are not transferred.
This solution not working: ...
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