All Questions
149,350
questions
-1
votes
0
answers
38
views
How to learn Python and Arcpy(ArcGIS Pro) from knowing nothing in a clear and efficient way? [closed]
I am a complete new to Python and Arcpy.
I have learned some knowledge about R before,such as raster and terra packages but now I think learning Python is much more difficult than learning R. And I ...
- 77
1
vote
0
answers
45
views
Converting heavy geopackage file to lighter format using QGIS
I have a 30GB geopackage file containing 1M least cost paths inside (single vectors). As I want to share this in a repository e.g. Zenodo, I need to transform it to a lighter and manageable format.
...
- 149
1
vote
0
answers
23
views
Getting massive residuals while trying to georeference an image
I have a TIFF of a historic map that I have downloaded, and this file already has projection information. The file's projection is EPSG:27700, which is the same as my project CRS. I am trying to ...
- 11
1
vote
1
answer
38
views
Converting working ModelBuilder to Python script reports errors in ArcGIS Pro
I want to learn Python and ArcPy by converting ModelBuilder to Python script.
First, I tried to use 'extract by mask' in this way.But it failed.
# -*- coding: utf-8 -*-
"""
...
- 77
1
vote
0
answers
27
views
Calculating average NDVI pixel-by-pixel
Ok, I have loaded a .tif file using python3. I calculated the NDVI by making calculations to the different channels of the .tif. I marked an area where I want to calculate the average NDVI. The ...
- 117
1
vote
0
answers
20
views
Using TIN Interpolation algorithm in PyQGIS
I was doing Tin interpolation using pyqgis, and this algorithm has this complex param called INTERPOLATION_DATA, where I'm stuck to create a valid string by the documentation described.
From what the ...
- 161
0
votes
0
answers
28
views
Recenter map that crosses international dateline with ggplot and geom_sf
Consider the map of Europe below. Parts of Russia are on the other side of the map. How might I "recenter" the map so that there is less empty space? I guess I need to somehow move the ...
- 101
2
votes
1
answer
26
views
Load WMS service into Mapbox map
I am able to add a WMS layer to a Leaflet map with very simple, readable code:
var wmsURL = 'https://opengeo.ncep.noaa.gov/geoserver/klwx/klwx_bref_raw/ows?';
var wdgProductLayer =
L.tileLayer.wms(...
- 43
0
votes
1
answer
17
views
Merging .tif files via gdalbuildvrt not working
I have a piece of code in R that I have used for a while now to transform .xyz files to .tif and then merge all those .tif files into one big .tif. It has worked well when I last used it 2 years ago, ...
- 31
1
vote
1
answer
35
views
Summing up fields with field calculator in PyQGIS
I am trying to sum up the content of the fields of my attribute table that have the string _Wert in their name. I tried to do it as shown in the following algorithm. But something is wrong with my ...
- 31
-2
votes
0
answers
24
views
I found 100% overall accuracy (OA) during classify of Sentinel 2 with GEE [closed]
I have tried to classify Sentinel 2 MSI 2A images using RF and CART Classifiers in Google Earth Engine, and also I have used 70% for training and 30% for validation but I found 100% overall accuracy (...
1
vote
0
answers
38
views
Add magnetic declination to print composer
Is it possible to let the QGIS print composer calculate the magnetic declination at the current map area and just display the value in the corner of the map? I have searched a lot but did not find any ...
- 11
0
votes
0
answers
27
views
Organizing GIS data on PostgreSQL [closed]
I have a set of data for different regions where for each region sample points are created and data are collected based various features of the soil such as chemical composition, soil structure, ...
- 11
4
votes
1
answer
80
views
How to set raster transparency in color range? - QGIS
I need to digitize some old maps. But when working, I need to make the backgrounds of old maps as transparent as possible. But the backgrounds of old maps are usually gray and shades of gray. I can ...
- 77
0
votes
0
answers
22
views
Export frequency histograms of each bands to CSV to different columns
I am exporting frequency histograms of the bands of my MODIS data.
lst = ee.ImageCollection('MODIS/061/MOD11A2').select(['LST_Night_1km', 'LST_Day_1km'])
sr = ee.ImageCollection('MODIS/006/MOD09A1')....
- 1
1
vote
1
answer
25
views
Spatial index creation in GeoServer when adding PostGIS store
If we are adding a GeoServer store using the shapefile section, it is possible to check the option so GeoServer creates spatial index files, Is this feature available when we add store using postGIS ...
- 11
1
vote
1
answer
23
views
Unable to get points from NetCDF even ogrinfo shows it has data
I need to extract point data to convert it to GeoJSON from a NetCDF file, the file seems ok when issuing ogrinfo ultimo.nc
INFO: Open of éultimo.nc'
using driver énetCDF' successful.
Metadata:
...
- 179
1
vote
0
answers
10
views
OGR_INTERLEAVED_READING error with gdal_rasterize
I've been trying to rasterize big PBF (1.2GB) file using gdal_rasterize and got this error:
ERROR 1: Too many features have accumulated in lines layer. Use the OGR_INTERLEAVED_READING=YES ...
- 11
3
votes
1
answer
86
views
Create attribute in a field based on the part of the name of a file in a folder with Python in QGIS
I have a common path (F:\Comune) where there are folders with name that corresponds to the attribute of a field of the vector Zp.gpkg called "Numero".
The field "Numero" for every ...
- 69
1
vote
1
answer
48
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 ...
- 11
0
votes
0
answers
28
views
Finding distance from settlement to river in ArcGIS Pro
I am trying to determine how to calculate which specific settlements are within a 30-minute walk from a river polygon on ArcGIS Pro. The country I am focusing on is Nepal, thus, elevation also needs ...
0
votes
0
answers
25
views
Multiplying binary rasters
I have 2 binary rasters: one of them contains buffer zones around evacuation roads and the other one contains buffer zones around rivers. I want to find out the areas located near the evacuation roads ...
0
votes
0
answers
30
views
Combine two raster datasets from different areas - xarray
I simply wish to combine two raster datasets from different spatial extents and with different coordinate reference systems using python. Eventually, I wish to combine enumerable datasets, but ...
- 150
0
votes
0
answers
15
views
QGIS and plugin Catalog on the fly
I upgraded QGIS from 3.16 to 3.22. Everything works fine, except that I’m not able to install the plugin « Catalog on the fly ».
I always have an error:
TypeError: decorated slot has no signature ...
- 680
1
vote
1
answer
43
views
QGIS won't launch on factory reset Dell with Windows 10 Home
I just acquired a Dell Inspiron laptop from a friend. It has Windows 10 Home. I did a factory reset, installed the QGIS standalone installer for 3.22.8. It installed successfully, but when I go to run ...
- 11
1
vote
1
answer
33
views
Using QGIS default Random Color Ramp in Categorized symbology using PyQGIS
Based on this code below, is it possible to use Random Color option in Symbology?
layer = iface.activeLayer()
field_name = 'zona_manejo'
field_index = layer.fields().indexFromName(field_name)
...
- 631
1
vote
1
answer
32
views
Creating a stack of annual images
I am working with the tropical moist forest dataset (https://forobs.jrc.ec.europa.eu/TMF/data.php#downloads) and I have a script where I can calculate the areas for a specific year based on landcover ...
- 11
-2
votes
0
answers
18
views
Uploading to USGS.GOV resulting in an error [closed]
I am trying to upload a shapefile to download Landsat imagery, but at each point I keep getting this error:
Please limit your Shapefile to 500 points.
0
votes
0
answers
20
views
DEM from Sentinel 1 C-band SAR
I have been using the standard protocol (ESA/ASF) to generate DEMs (actually DSM which is what S1 C-band gives) from Sentinel-1 C-Band SAR tiles. My locations are in the Eastern Himalayan foothills (...
- 11
1
vote
0
answers
18
views
Relation aggregate using /n as concatenator? [closed]
relation_aggregate(
'S1Structur_SD_Sondages20_Num',
aggregate:='concatenate',
expression:="description_us",
concatenator:='\n'
)
I want to use a linebreaker as concatenator.
...
- 383
2
votes
3
answers
51
views
Extract duplicate points
I'd like to know how to extract duplicate points (geometrically overlapped) of a point layer, using field calculator of QGIS.
I can extract one or both the duplicates points, is indifferent. Any ...
- 683
0
votes
0
answers
24
views
Street Survey via LiDAR - Hole Volume Determination [closed]
I am a bachelor's student and currently working on my thesis.
My data is a 3D object of a street, from which I hope to be able to calculate the volume of all holes/ruts/depressions present.
Until now, ...
0
votes
0
answers
16
views
Joining tables in ArcMap
What I am trying to accomplish is displaying the location of parcel numbers from an Excel table on a map. I have a shapefile with all the city parcels already mapped out so I was going to try and join ...
- 1
3
votes
1
answer
37
views
Add a linebreak after a fixed sequence in a text field
I have text field that contains data in this format
1001.01:abcdefgh.1001.02:abcdefghijkl.1001.03:abcdefghfsdqfs.
I would like to insert an automatic line break so the result would be this :
1001.01:...
- 383
0
votes
0
answers
18
views
Transparant area when TIFF overlap in an image mosaic GeoServer [closed]
I have set up an image mosaic in GeoServer that show three TIFF ortophotos. The TIFFs are made in WEBOdm. When I preview the Layer it show they are transparent on top of the other tiff`s where they ...
0
votes
1
answer
14
views
Select By Location only shows layers in my inset map [closed]
I have two data frames. One called layers and one called state inset. When I try to use select by location, the only layers that are listed are the ones in the state inset data frame. If I ...
- 61
0
votes
0
answers
22
views
Load value in QGIS form field [closed]
I would like to know if it is possible to load a value in a field when I select an option from the combobox of a QGIS form. This is my form:
1
vote
1
answer
20
views
Extrapolate URI from a WFS connection
Purpose: to create and add a vector layer instance to the project with Python
This is what is written in https://docs.qgis.org/3.22/en/docs/pyqgis_developer_cookbook/loadlayer.html#id1 to connect with ...
- 69
3
votes
2
answers
69
views
QGIS - symbol transparency not working when using string-defined fill colour
I want to fill and outline polygons by using a field that contains HEX codes as a string, e.g. #99d594, as well as set the fill opacity to 25%.
I'm able to set the colours with the right field through ...
- 33
0
votes
1
answer
16
views
Adding field and calculating field values based on a current field using ArcPy [closed]
I created a new numeric field (FloodValues) and need to populate that field based on values from an existing text field (ClassName). There are seven different values in ClassName field so I need to ...
- 9
1
vote
0
answers
26
views
Cannot undo or redo (greyed out 95% of the time)
QGIS is amazing, but I cannot undo or redo on basic actions. Here is only one example.
I have 5 layers in my project, and I turn one layer off. I cannot undo with control + z or edit>undo.
I am on ...
- 11
3
votes
2
answers
40
views
Plotting a categorical terra raster with a colour map
I'm trying to plot a categorical terra raster object with an explicit colour for each level, like you'd do with a land cover raster, but running into problems when the raster doesn't have every level ...
- 52.1k
1
vote
1
answer
23
views
Error generating chart: User memory limit exceeded
I want to generate a vegetation indices Time series chart and the AOI is not that big which might be the problem for the chart not being generated. Secondly, the CSV exporting keeps refusing to export ...
- 29
0
votes
0
answers
21
views
2D geologic cross section in QGIS using qProf
I want to use qProf/QGIS to create a geologic cross section, where the depth of a geologic layer is shown. But for that I only have the information of boreholes at which depth my geologic layer begins....
- 13
1
vote
0
answers
15
views
Mask NetCDF file data with multiple variables from shapefile in Python
Most of the solutions to this I've seen online only work on 3-D time series data, but my NetCDF files has more than one variable.
It has a data variable named Albedo and I need to plot it using a ...
1
vote
2
answers
45
views
Bare soil detection using drone images
I'm working with drone images which separated to red, green and blue bands. My task is to determine bare soil pixels. I've tried to swap bands in the composite, and calculate different differences ...
- 21
-1
votes
0
answers
30
views
Setting up ArcGIS Pro 3.0 Python env in PyCharm - Can´t import arcpy module
I'm trying to set up PyCharm to work with the Python environment (Python 3.9.13) installed with ArcGIS Pro 3.0 on a new computer (Win 11). I've tried cloning the environment both from within ArcGIS ...
- 49
1
vote
1
answer
26
views
Checking intersection between polygon and geometry in GeoJSON
I have a GeoJSON file with different geometries(polygons). I'd like to find if my polygon intersects with any of the file's geometry.
I am not going to paste the file here as it is a long one, but can ...
- 13
-1
votes
0
answers
32
views
Plot graph as subplots for multiple csv files [closed]
I have multiple CSV files. All contains the same columns. Column's names are Date and Value. Now I want to plot graphs for each different CSV and as different subplots and want to save them in png ...
1
vote
1
answer
29
views
How to obtain coordinates for all the selected point data?
I have a selected points and I want the syntax for the finding the coordinates for the point data.
import arcpy
arcpy.env.workspace = "C:/Users/Desktop"
in_point2 = 'C:/Users/...
- 19