All Questions
133,223
questions
0
votes
0answers
6 views
Losing attribute table when working remotely
Because of the pandemic my work is strictly remote. I remote into my work computer via laptop. I have two monitors connected to that laptop. Sometimes when I move the arcmap desktop program from one ...
-4
votes
0answers
15 views
Struggling with assignment question
I am having trouble trying to answer this question: list 5 key data issues to be considered when outsourcing GIS data from the internet, describes the process that you would use to address each of the ...
0
votes
1answer
7 views
EVI or NDVI collection image donwload
Landsat 8 Collection 1 Tier 1 8-Day EVI Composite.
I continued with the starting codes given by Google Earth Engine. I tried to solve my work by adding code to the rest of these codes. However, it ...
0
votes
0answers
9 views
Multiple raster calculation in QGIS with Python script
I would like to run this code for importing 3 different rasters at every loop and do the calculation between them, but the code doesn't work (the writing "invalid layer, GDAL provider cannot open ...
0
votes
0answers
5 views
r.to.vect not working after thinning QGIS
I started with a raster layer, then reclassified it using r.reclass. I thinned using r.thin (took ages- big file?), then tried r.to.vect and I'm still getting an error message telling me I need to use ...
0
votes
0answers
12 views
Is it possible to use a table for translating through BioStrings in R? [closed]
I have a table of contig ID's and their associated DNA sequence and I would like to turn that into amino acid sequences using the translate function from Biostrings. I keep getting error messages when ...
0
votes
0answers
16 views
Setting layer properties through PyQGIS
I have to config several project files with many layers in each one, many of those layers have similar fields which should have the same forms configs.
Is there a way to config forms attributes to ...
1
vote
0answers
7 views
Is this ST_Relate result expected?
The following PostGIS query involving ST_Relate gives FFFFFF102 as its result:
SELECT ST_Relate(
ST_GeomFromText('POLYGON EMPTY'),
ST_GeomFromText('MULTILINESTRING((0 0,0 1),(0 1,1 1,1 0,0 0))'),
...
1
vote
1answer
23 views
Convert all files in a Linux directory from NITF to PNG using gdal_translate
I have a directory called /home/john/WAMI/WPAFB_TRAIN/ with .txt files that have names like:
20091021202517-01000100-VIS.ntf.r0
20091021202517-01000101-VIS.ntf.r0
I know that the code needs to say ...
0
votes
0answers
12 views
GDAL Python, projecting WGS84 geom to UTM to find area
I'm writing code with GDAL in Python. I'm trying to find the area of a geom in WGS84 with GDAL. I tried projecting it to UTM and then getting the area of the projection, but the answer isn't what I ...
0
votes
0answers
17 views
How to make ocean drainage map using python
I'd like to make ocean drainage map like this:
In particular I'm interested in Russia.
A relatively explicit data source is hydrosheds.org, however from there i can get data to display only endorheic ...
2
votes
0answers
8 views
How can I get values from a array (which is evaluated by spatial query) as default-values in other fields
In QGIS 3.16.0 I have a postgis-polygon-layer with a field "array_polygon" which contains an array.
When digitizing a postgis-point-layer-point I would like to use the different array-values ...
-2
votes
1answer
13 views
How to import Python packages in PyQGIS?
I was trying to import fuzzywuzzy but I was getting a module not found error.
0
votes
0answers
10 views
Error generating chart: No features contain non-null values of “system:time_start” Create NO2 chart with unit ton/m2 in GEE Sentinel-5p
I'm using the below code to create NO2(Sentinel-5p) time series charts for my region of interest by mean reduction. However, upon charting, I get an error message
Error generating chart: No features ...
0
votes
0answers
7 views
Row or Col is too big on this zoom level when implementing HERE Satellite tiles
I have successfully implemented OSM maps and now looking to do the same with the HERE service for aerial imagery. From the research I have done it looks like the main issue is the Y axis being ...
1
vote
0answers
11 views
How do I compute the line of equal distance among several polygons in R
I have a simple GIS problem I was not able to find the solution on the internet.
My aim is quite simple: I have a polygons layer that contains several entities, and I would like to compute a new layer ...
0
votes
0answers
10 views
On the calculus of the variable “autocov” from spdep package
I’m facing a spatial autocorrelation problem and I want to calculate the « autocov» covariate through the function autocov_dist from spdep package. The problem is when I defined the neighborhood ...
0
votes
0answers
7 views
Speed up pgr_dijkstraCost
I have a pgRouting network graph of ~ 1 mio edges and ~ 0.4 mio vertices. I want to find out something like "nearest facility" for bigger subsets.
E.g. i have a bigger number of source ...
1
vote
1answer
13 views
QGIS 3.4 Vertex tool highlight colour change
I can change the colour for selected items fine. I have even figured out how to change the colour of the preview when moving a vertex. How can I change the colour of the highlight when hovering over a ...
0
votes
1answer
13 views
How do I calculate average depth of a 250m square using points at 125m spacing using QGIS
I have a set of points spaced at 125m intervals across an area, an average depth value is assigned to each point. I need to calculate from these points a single average depth value for a 250m square, ...
3
votes
1answer
44 views
Convert a Fill Symbol into geometry generator symbol using PyQGIS
I am trying to use PyQGIS to convert a Fill Symbol Layer into a geometry generator Symbol Layer in a rule-based renderer with 300 rules.
I am able to iterate over the rules and return each rule's ...
3
votes
2answers
24 views
Save x,y,z values to a GeoJSON file from QGIS
I would like to save x,y,z values for polygon vertices as a geoJSON file using Python in QGIS. I've made several attempts, but all have issues. I've found that the QgsPoint object must be used as ...
0
votes
0answers
8 views
Create NO2 chart with unit ton/m2 in GEE Sentinel-5p **Error generating chart: No features contain non-null values of "system:time**
I'm using the below code to create NO2(Sentinel-5p) time series charts for my region of interest by mean reduction. However, upon charting, I get an error message
Error generating chart: No features ...
2
votes
1answer
15 views
Adding field by proximity using ArcMap
I'm using ArcMap with the Basic license.
I have turnout gates (points) on or very close to irrigation facilities (lines). The irrigation facilities have a field for type (canal, pipeline, culvert, etc....
0
votes
0answers
13 views
how to use PostGIS functions with geometry(MultiPolygon)? [closed]
org.geotools.jdbc.JDBCDataStore stores a shapefile in a PostgreSQL database as a geometry(MultiPolygon). I am trying to use PostGIS functions such as ST_Contains on the geometry(MultiPolygon) but it ...
3
votes
0answers
22 views
PyQGIS: how to stop script processing without shutting down QGIS
I'm looking for a way to aborpt a script execution if a sql query returns some results. I've found a few solutions on the forum but all of them lead to shutting down QGIS (thing I precisely want to ...
3
votes
0answers
19 views
QGIS Processing algorithm output
I am developing a plugin in QGIS using Python language. This plugin uses algorithms from Processing Toolbox and I save some results in the temporary folder assigning "QgsProcessing....
4
votes
0answers
19 views
Georeference single drone image from EXIF data
Looking for an algorithm (python, formulas, whatever...) to georeference a single drone image based on its EXIF data.
Specifically, I need to translate drone GPS latitude and longitude (after ...
1
vote
0answers
7 views
Gdal translate HDF5 to GeoTIFF library funtion
Im am trying to convert a radar file provided in HDF5 to a GeoTIFF using gdal.Translate() in my Python script.
An example of the HDF5 file can be downloaded here
I have already managed to get it ...
0
votes
1answer
22 views
Landscape change metrics for vector data
I am new to GIS.
I am currently working on a problem which involves two vector datasets about habitat and land use ("now" and "future"). I need to generate metrics like "...