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6 votes
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Convering latitude and longitude of starting point of line from Lambert to DMS in QGIS

There are built-in functions to get the start and end points: y( transform( geometry:=start_point($geometry), -- use the `start_point` or `end_point` function here source_auth_id:...
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6 votes
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Converting PNG to GeoTIFF using GDAL Python

I'm assuming that your PNG file doesn't have geolocation information embedded but you know what the corners of the data. I think you just had the wrong option for gdal.Translate. Check this out using ...
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5 votes
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Converting from MultiPolygon to Polygon in PostGIS

If you want to Ignore the edge cases, and get only the First (or only) Polygon, from the MultiPolygon geometry, then you need to use the ST_GeometryN() function. A query like the following will give ...
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5 votes
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Converting grid corners from UTM to degrees, minutes, and second in QGIS

You can use these expressions: left: to_dms(x_min(transform($geometry,layer_property(@layer,'crs'),'EPSG:4326')),'x',3) top: to_dms(y_max(transform($geometry,layer_property(@layer,'crs'),'EPSG:4326'))...
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5 votes

Convert date/time format

A Field Calculator expression tested in QGIS 3.16.16 array_to_string(array_reverse(string_to_array(left("created", 10), '-')),'.')+' '+substr("created", 12, 2)+':'+substr("...
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5 votes
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How do I translate MapBox GL JS GPS coordinates into SWEREF 99 TM ones?

Library proj4.js (http://proj4js.org/) is usually used for coordinated transformation in JS. To use it one needs CRS definition, which can be easily found on epsg.io site. SWEREF 99 TM coordinate ...
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  • 17k
5 votes
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Converting number with leading zeros in integer in QGIS

Try this expression with the to_int() function: to_int("baumnummer") -- to_int('000001') -> 1 If you wish to maintain the string field type, you could expand the expression above with ...
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  • 24k
4 votes
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Converting to a CRS and the back to the original CRS, not the same original coordinates

Proj4Net seems to be a port of Proj4J that is a port of Proj.4 https://trac.osgeo.org/proj4j/. The Proj.4 library is using EPSG:4326 as a pivot coordinate system so the conversion from EPSG:2105 into ...
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4 votes
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Converting CSV file with polygons in dictionary format into GeoDataFrame

I read the CSV file into a Pandas' DataFrame, extract the numbers from your boundary column, convert to shapely polygons, convert Pandas df to GeoPandas gdf: import pandas as pd import geopandas as ...
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  • 52.1k
3 votes

Converting PNG to GeoTIFF using GDAL Python

I know that the OP specifically asked for a gdal solution but may I offer another solution that works better for me ? Here I'm using the rasterIo lib (available on both pipy and conda) to read the png,...
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3 votes

QVariant error when converting DataFrame into attribute table using PyQGIS

A standalone sample correction. The issue is the fact you try to fill QGIS content using for integer a <class 'numpy.int64'> (due to pandas type) whereas it should be a native Python int. The ...
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3 votes
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QVariant error when converting DataFrame into attribute table using PyQGIS

I believe it is because you are passing Pandas datatypes to the attributes of the QgsFeatures. import pandas as pd ## make a toy dataframe data = [[0, 'Very'], [1, 'Little']] df = pd.DataFrame(data, ...
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  • 7,291
3 votes

An observation regarding conversion between geodetic latitude and geocentric latitude

If the Earth were spherical, of homogeneously distributed mass, rotating at constant angular velocity, alone in the universe without the influence of other celestial bodies, we could mathematically ...
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3 votes

Recursively reproject shapefiles in folders and subfolders

On Linux systems it is fairly easy, provided there is an easy regex that describes the folders with the shapefiles in. ogr2ogr will create a new geopackage and add a table for each spatial file it ...
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  • 75k
3 votes
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Convert date/time format

While @Kazuhito's answer works perfectly, I just wanted to add an alternative solution using to_datetime to make a datetime object and format_date to convert it back to a formatted string: format_date(...
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  • 7,291
3 votes
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How to create a polygon from a CSV file with coordinates using PyQGIS?

Read the attributes into a list of QGSPointXY's using getFeatures : points = [QgsPointXY(f['long'], f['lat']) for f in iface.activeLayer().getFeatures()] poly = QgsGeometry.fromPolygonXY([points]) #...
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3 votes
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Converting XYZ file to shapefile using Python

I have numerous XYZ files, which aren't gridded from GDAL XYZ – ASCII Gridded XYZ GDAL supports reading and writing ASCII gridded XYZ raster datasets (i.e. ungridded XYZ, LIDAR XYZ etc. must be ...
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  • 51k
2 votes

Saving raster layer from GeoPackage results in large GeoTIFF file

I assume that the raster data in the input GPKG was compressed, while you did not set any compression when exporting the raster to GeoTIFF format. Check out the GeoTIFF format creation options: https:/...
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  • 515
2 votes
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GEE Converting Units of the FLDAS Precipitation data (Rainf_f_tavg) from kg m-2 s-1 to mm/month

You are trying to apply the .expression to the entire ImageCollection. Unfortunately .expression can only be applied to an ee.Image() object so you have to map your function over the entire image ...
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  • 1,837
2 votes

Recursively reproject shapefiles in folders and subfolders

This will reproject all shapefiles then package them into geopackages, one for each folder with shapes. For example I get the geopackages /home/bera/Downloads/shape/svk/riks/riks.gpkg /home/bera/...
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  • 52.1k
2 votes

Converting DEM raster (NetCDF file) into point cloud (LAS file) using Python

Check this out. This solution works if you have your DEM as TIFF format. But if you can extract the XYZ coordinates from the NetCDF file yourself and save it to a text file, then you can use LAStools ...
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  • 162
2 votes

Converting raster (.tif) to ASCII format using ArcMap

Make sure you have the same symbology setting on the asc raster as the tif. The actual values can be the same but the symbology can make them appear different.
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  • 52.1k
2 votes

Converting shapefile into raster with desired pixels 1km²

Your question in lacking details like whether you want to use an attribute as raster value or specify it manually. In both cases, search for "Rasterize": If you want the pixels to overlap ...
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2 votes
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Converting coordinates in Harrisburg (Pennsylvania) to WGS84 using GeoPandas

The coordinates I have are in feet, in the coordinate system NAD83 / Pennsylvania South (ft US). The EPSG code for it is EPSG:2272. I found that out by trying the epsg code of a data set I have for ...
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2 votes
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Converting text file into GeoJSON using Python

I think using geopandas is a more convenient way to create GeoJSON. Once you convert your txt to coordinates, you need to do some preliminary work. This is the process of handling str in pandas. ...
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  • 588
2 votes
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Map lat/lon onto polar stereographic projection map based on two known points on map image

The dataset is documented in "MANAIR Manual of Standards and Procedures for Aviation Forecasts: appendix C" -- Appendix C: Graphic Area Forecast (GFA)—Supplement to Chapter 4. A coordinate ...
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  • 3,463
2 votes
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Workflow to convert Python script without UI file into QGIS Plugin

Inspiration for this answer was found in @J.Monticolo's comment So, for me, put the startup.py file into a your_plugin_name_or_whatever.py, do a function called def launch_code and put the startup.py ...
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  • 24k
2 votes

Convert Coordinate Notation warning, empty output

Your three lines of sample data worked for me with Input coordinate system: WGS_1984_UTM_Zone_10N Input coordinate format: UTM bands X Field (where the data is) UTM If the warning is being cause by ...
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1 vote

Retrieving FLDAS evapotranspiration data (NASA/FLDAS/NOAH01/C/GL/M/V001) via GEE and converting units to mm/year

Yes, there are several issues in your code. You should use an ee.Reducer for getting evaporation values instead images. First of all, I'm going to review units. Units in kg m-2 s-1 are equivalents to ...
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  • 26.2k
1 vote
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Converting float image to 8bit using GEE

You can use the following code line: var image8b = image.unitScale(-3, 3).multiply(255).toByte(); Be sure to select the appropriate unit scale. I have used (-3, 3) because I don’t really know the ...
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  • 1,207

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