Questions tagged [transform]
The transform tag has no usage guidance.
29
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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 ...
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32
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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/...
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56
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Discrepancy In PostGIS Transformation: 103761 to 900913 to 4326 vs 103761 to 4326
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 ...
- 119
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116
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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 ...
- 21
1
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2
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326
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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 ...
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4
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1
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132
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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 ...
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136
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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 ...
4
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59
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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 ...
- 2,232
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51
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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 ...
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207
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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 ...
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108
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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=...
2
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1
answer
516
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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 ...
- 31
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283
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'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(...
- 679
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2
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365
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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 ...
- 2,252
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93
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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 ...
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571
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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 ...
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96
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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 (...
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190
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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 ...
- 137
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636
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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-...
- 103
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173
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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 ...
3
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1
answer
265
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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=&...
- 309
2
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1
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227
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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(...
- 145
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1
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620
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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 ...
- 133
1
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1
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714
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"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 ...
- 11
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1
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1k
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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, ...
- 173
7
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1
answer
3k
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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 ...
- 71
1
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1
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1k
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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 ...
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2
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687
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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 ...
0
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2
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600
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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 ...
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