Questions tagged [transform]
The transform tag has no usage guidance.
22
questions
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0
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21
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 ...
0
votes
1
answer
14
views
Change the CRF used in a shapefile , and save the modification with Java Geotools [closed]
I want to write a function in Java using Geotools, to reproject a shapeFile in a specified CRF , and save the modification in the ShapeFile,
So the input will be a shapefile using for example ESRG:...
1
vote
1
answer
26
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(...
5
votes
2
answers
136
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 ...
0
votes
1
answer
19
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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 ...
0
votes
0
answers
77
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 ...
1
vote
0
answers
32
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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 (...
0
votes
1
answer
50
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 ...
0
votes
1
answer
80
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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-...
0
votes
1
answer
48
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 ...
2
votes
0
answers
64
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=&...
2
votes
1
answer
79
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(...
1
vote
1
answer
148
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 ...
0
votes
0
answers
37
views
Orientation Conversion: ECEF YPR (321) to LTP Tait-Bryan angles
I am looking for guidance to convert ECEF orientation (Yaw/Pitch/Roll 3-2-1) to the corresponding LTP (NED/ENU) Tait-Bryan angles.
There are several excellent resources to convert position between ...
1
vote
1
answer
167
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 ...
1
vote
1
answer
235
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, ...
0
votes
0
answers
43
views
How to reproject without shifting image?
Reprojecting an image shifts it by about 200m. I think this is because the reprojection changes the transform if I specify the scale.
I am hoping to change the resolution of the image (e.g. to a ...
3
votes
0
answers
875
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 ...
1
vote
1
answer
163
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 ...
0
votes
0
answers
31
views
Applying the same transformation to a Raster as a Point Cloud
I am using PDAL filter.transformation to apply the same transformation to all my point clouds.
pdal pipeline example:
[
"untransformed.las",
{
"type":"filters....
3
votes
2
answers
259
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 ...
0
votes
2
answers
244
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 ...