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3 votes
3 answers
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Aligning surveyed point layers in QGIS

I’m wondering if QGIS has a tool to align the lat, long, and alt data of two point layers based on a common point. I have data like this: Survey 1 points: A B C Survey 2 points: C D E I’d like to ...
Skookum's user avatar
  • 31
3 votes
0 answers
48 views

Adding custom CRSs and coordinate transformations QGIS (modifying the CRS/CT catalog)

I am trying to add custom CRS and transformation definitions to the CRS/CT catalog in QGIS. As far as I know, the qgis.db is meant to handle custom definitions. However, it does not contain a table ...
phaarnes's user avatar
0 votes
0 answers
15 views

gdal ogr transform c++ swaps axis order x to y [duplicate]

This is example #include "gdal/gdal.h" #include "gdal/ogr_spatialref.h" #include <iostream> void TransformBounds(double xmin, double ymin, double xmax, double ymax, ...
Vignesh M's user avatar
4 votes
1 answer
93 views

pyproj.Transformer.from_pipeline inverse / Using EPSG transformation code how to invert?

I have been trying to use PROJ as an an alternative confirmation of correct parameters when doing transformations (either by spreadsheet or third party software). Typically we will get instructed by ...
marky9074's user avatar
1 vote
0 answers
49 views

Change layer CRS without displacing relative locations with regard to old CRS

I have some points with projected CRS EPSG 3003 (Italy) and I'm displaying them in QGIS on a project map with CRS 3003. If I export the same points with projected CRS EPSG 7791 (Italy) and load them ...
Michele Cordini's user avatar
1 vote
0 answers
77 views

User defined transformation in QGIS

Is it possible to define custom transformations within QGIS, such as for user-defined CRSs? If this cannot be accomplished directly through the graphical user interface, might there be an alternate ...
phaarnes's user avatar
1 vote
0 answers
47 views

QGIS Australia GDA94 to 2020 Transformation File (NTv2_3>

I'm looking to convert some Australian GIS data from GDA 94 to 2020. The reprojection exists, but I need to use a particular transformation - specially NT v2_3 Conformal (this exists in ESRI). I ...
Amit's user avatar
  • 11
2 votes
0 answers
80 views

Transform coordinates from ITRF2014 (2020.39) to ITRF2008 (2010.0) using PROJ4?

Due to the fact that I cannot convert the coordinates obtained at epoch 2023.39, X = 1710698.054 meters; Y = 3046082.270 meters; Z = 5318707.282 meters, I still cannot understand how to use in this ...
El_Faie's user avatar
  • 21
1 vote
2 answers
340 views

Transforming from NAD83(2011) or from WGS84 gives the same result (pyproj)

I'm trying to transform (using pyproj) the same coordinates, first from WGS84, and then from NAD83(2011), and I'm getting the same result: from pyproj import CRS, Transformer from_wgs84_transformer = ...
paul's user avatar
  • 11
0 votes
2 answers
546 views

Transforming geometry from EPSG:4326 (source CRS) to EPSG:3857 (target CRS - Leaflet's OSM default CRS)

My problem is I tried transforming from EPSG:4326 to WGS84, and it worked (just swap the axis order), and I also tried transforming from EPSG:4326 to EPSG:3875, and it worked too (the coordinates ...
Harry's user avatar
  • 11
1 vote
1 answer
806 views

Converting between WGS84, SK42 and ED50 geodetic reference datums

I need to convert between WGS84, SK42, and ED50 geodetic reference datums in either a UTM or MGRS coordinate system given GPS coordinates I've been using pyproj for the conversion by finding the EPSG ...
Christo Labuschagne's user avatar
0 votes
1 answer
484 views

Read GeoJSON object in a CSV file column and transform it to geometry

I have a column ('geo_shape') that contains GeoJSON object type of linestring geometry and, so far, I didn't manage to read and transform it to a GeoPandas/shapefile type of geometry. Here is a way ...
SKSLH's user avatar
  • 1
0 votes
1 answer
166 views

How can I use code to get accurate "crs_transform" of ee.Images after the clip() operation?

I use GEE(Google Earth Engine) for my research. I found that the parameters "crs_transform" of the ee.Image did not change before and after the clip() operation. print(ee.Image('LANDSAT/LC08/...
he lirong's user avatar
1 vote
0 answers
148 views

Discrepancy In PostGIS Transformation: 103761 to 900913 to 4326 vs 103761 to 4326 [closed]

Overview I'm using PostGIS 3.1 on PostgreSQL 12.14 and I'm facing an issue with GIS data transformation and I need some assistance in understanding the cause of a significant discrepancy between two ...
jBit's user avatar
  • 119
1 vote
1 answer
224 views

Reproject and resample raster1 to CRS and grid of raster2, but keeping the shape of the original raster

I am working with two raster files. path_target: shape (27502, 6133); CRS: EPSG 31255 wk_path: shape (294825, 570431); CRS: EPSG 31287 I would like to reproject path_target to EPSG 31287 and align the ...
KevinKo's user avatar
  • 21
1 vote
2 answers
568 views

Create pandas DataFrame from raster image - one row per pixel with bands as columns, preserving coordinates [duplicate]

I have a 37 band image that I hoping to transform so that each row is a pixel and each column a band. I am following what was suggested in this post: Create pandas DataFrame from raster image - one ...
Greta Martin's user avatar
5 votes
1 answer
162 views

QgsCoordinateTransform causes crash in processing script

I want to perform a QgsCoordinateTransform on a QgsGeometry object and do some operations on this afterwards. I am doing this in a processing script and am getting the original QgsGeometry object from ...
MrXsquared's user avatar
  • 34.9k
0 votes
0 answers
158 views

I am trying to convert 3D world coordinate to a 2D image coordinate in the form of pixels

I have a GeoTIFF file. I am trying to convert 3D world coordinate to a 2D image coordinate in the form of pixels. How can I do that? Suppose, I can extract latitude, longitude and elevation data from ...
keeponlearning101's user avatar
4 votes
0 answers
95 views

How to reduce the clothesline-effect in ST_Transform?

When we use standard ST_Transform (e.g. PostGIS implementation), from a SRID to another that curves straight lines, the original straight lines represented by two points, that must be transformed into ...
Peter Krauss's user avatar
  • 2,304
1 vote
1 answer
68 views

How may one convert from Lo.22/18 Prelim. to Schwarzeck / Lo22/17: EPSG29377?

I am currently georeferencing an archival map with a set of coordinates from a Documents. Some of the coordinates are given in Schwarzeck / Lo22/17, the other points however are given in Lo22/18, a ...
I Love Mapping So Much's user avatar
1 vote
1 answer
317 views

How to convert WGS84 to NAD27 in pygeodesy?

Using PROJ, this command will convert / reproject / transform a WGS84 latlon point to NAD27 CONUS, UTM zone 11: cs2cs.exe +proj=latlong +init=EPSG:4326 +to +init=EPSG:26711 -120 39 240281.39 ...
Tom Grundy's user avatar
0 votes
0 answers
166 views

st_transform does not work

I am trying to transform a geometry from srid 4326 to 26915. SELECT ST_Transform(s.geompos, 26915) FROM sites s But i got error : ERROR: could not form projection (LWPROJ) from 'srid=4326' to 'srid=...
عبد القادر كعوان's user avatar
2 votes
1 answer
864 views

C# GDAL spatial transformation (reprojection) always fails

I have a C# project that may load several vector data files and then needs to transform the spatial reference system (whichever used) to WGS84. I tried mostly the way described here, and also cannot ...
BAGZZlash's user avatar
1 vote
1 answer
436 views

'Affine' object does not support item assignment (rasterio)

I would like to change the resolution of cells in the transform slot of a raster file, but it seems I cannot just do that with simple variable re-assignment. import rasterio ftdm = rasterio.open(...
hmnoidk's user avatar
  • 707
5 votes
3 answers
640 views

Flipping polygon around arbitrary axis in QGIS

I want to flip a vector polygon about an arbitrary axis. What I would like to do is select the polygon to flip, pick two points (A & B in image below) identifying the axis about which the flip ...
cm1's user avatar
  • 2,290
0 votes
1 answer
105 views

Enlarging gBuffer width changes polygon shape

I am having some issues with spTransform and the gBuffer function. I basically have a polygon that I want to buffer with gBuffer (not with st_buffer for other reasons). For some reason the shapefiles ...
Lydia's user avatar
  • 9
0 votes
0 answers
806 views

Transform coordinates length to pixel length?

Is there a function to transform a coordinates length to a pixel length? I need this function for cropping and scaling map images to be inserted as layers in an OpenLayers Map. The map images are ...
Suka's user avatar
  • 81
1 vote
0 answers
122 views

Visualize transformation when reprojecting from Mercator to equirectangular

I am trying to visualize the map distortion that occurs when reprojecting from Mercator to equirectangular coordinate systems. The actual reprojection is not difficult, but I want to save images (...
EvoBio721's user avatar
0 votes
1 answer
295 views

How to generate ov2 poi programmatically from csv source

I'm looking at how to generate an ov2 file programmatically. Mainly I use python and I found something like this. But that kinda vague. I can't find documentation on how the file is build up. Also it ...
botenvouwer's user avatar
0 votes
1 answer
969 views

GDAL coordinate transformation using C/C++ API (OGRCoordinateTransformation)

I'm in a puzzle of figuring out how to create correct coordinate transformations using GDAL C/C++ API. I have referenced code from tutorial - https://gdal.org/tutorials/osr_api_tut.html#coordinate-...
arapEST's user avatar
  • 103
0 votes
1 answer
257 views

GeoTools: Geo Transform incorrect

I am transforming a coordinate between Lambert Conformal and WGS84. The values returned by GeoTools do not seem correct. From: PROJCS["unnamed", GEOGCS["Coordinate System imported ...
Chad Johnson's user avatar
3 votes
1 answer
367 views

Wrong transformation between British National Grid and WGS84

I have access to a remote DB with the following specifications: PostgreSQL 11.12 POSTGIS="2.5.2 r17328" [EXTENSION] PGSQL="110" GEOS="3.7.0-CAPI-1.11.0 673b9939" PROJ=&...
GStav's user avatar
  • 309
2 votes
1 answer
249 views

Converting latitude and longitude in a rectangle area in R?

I'm really struggling in how can I transform my lat and lon coordinates of my dataframe in x and y (Euclidean coordinates), where the x-axis should vary between 0 and 10. Here is my data: library(...
Ga13's user avatar
  • 155
1 vote
1 answer
774 views

Affine transformation: rescaling alters the raster bounds?

I'm trying to rotate a raster around its center coordinates, rescaling the resolution by a factor. I expect the transformation to conserve the center pivot. However; it seems that after the rotation ...
WaterFox's user avatar
  • 133
1 vote
1 answer
876 views

"ValueError: negative dimensions are not allowed" when using raster created from points in CSV

My problem is similar to "ValueError: negative dimensions are not allowed" when using raster created from NetCDF I am working on a raster that I generated from the interpolation of some ...
dncardenasg's user avatar
2 votes
1 answer
2k views

EPSG:3857 units are in meters, why is ST_Distance showing distant locations to be less than a meter apart?

According to Google, these two points are about 137 meters apart, yet the result of ST_Distance reports just a fraction of a meter? The units of the result should be in meters, as I understand it, ...
vaer-k's user avatar
  • 173
7 votes
1 answer
4k views

QGIS: No transform available error

I installed QGIS 3.16 on Ubuntu-20.04. Details on 'About QGIS': QGIS version 3.16.12-Hannover QGIS code revision be6cb030ac Compiled against Qt 5.12.8 Running against Qt 5.12.8 Compiled against ...
HY K's user avatar
  • 71
1 vote
1 answer
2k views

geometry.transform() removes the drawn feature in OpenLayers

I have a simple OL-based map with the default EPSG:3857 projection and an interaction which lets me draw a LineString on the map. Then, I have an event listener registered on the VectorSource, which ...
BaldWin03's user avatar
3 votes
2 answers
910 views

Array for_each in QGIS

Is there an expression in QGIS for array for_each to get the element from the output of geom_to_wkt($geometry) of the polygon and correspondingly transform the element (using the expression of LAT ...
ROEL SANTIAGO's user avatar
0 votes
2 answers
817 views

Type error for gdal- GDAL-style transforms have been deprecated

I'm trying to export numpy ndarray that I have to TIFF using rasterio. I have the transform of the image: print(transf) >>>(583932.1992386435, 10.0, 0, 2223772.1491772938, 0, -10.0) When I ...
ReutKeller's user avatar
  • 2,169