All Questions
147,996
questions
-1
votes
0
answers
10
views
How to draw a scale or a graduated marker on QGIS?
I need to place points at regular intervals on a map. How can I proceed?
In order to have regular spacing and have my rectangles all aligned, I need a tool to place my points with regular spacing. So ...
-2
votes
0
answers
5
views
Snowflake is giving 0 result when geometry is greater than extent
I have front end applications from where I get bounding box, which then I pass to ST_Intersect function ..
It works fine when the bounding box is within WGS84 Bounds.
But it gives 0 result when extent ...
- 317
0
votes
0
answers
4
views
Getting the WKID/EPSG code as dynamic text in ArcGIS Pro Layouts
I'm trying to get the WKID/EPSG code of the Coordinate System/projection used in the map as dynamic text in a ArcGIS Pro layout.
It should look something like this:
ETRS 1989 UTM Zone 33N N-zE (EPSG: ...
- 1
0
votes
0
answers
14
views
Why would anyone use Arcgis Server instead of GeoServer/Qserver etc for a simple map?
My team is building a web application which uses maps to track various object.
We should be able to draw moving entities, draw lines/ploygons, measure distances and areas.
No any fancy analysis beyond ...
- 19
0
votes
0
answers
6
views
Append original shapefile projection definition to GeoJSON using Javascript
In our web application we upload shapefiles and convert them into geoJSON format.
These shapefiles will be in different projections and I want to be able to add the original projection of the ...
- 1
0
votes
0
answers
10
views
Can I use the dropdown list in attributes table for several selected features in one time?
I use some dropdown lists for several attributes. Now I want to select several features (objects) and edit a field using the dropdown list. Is there a way to do it in one time, because it looks like ...
1
vote
1
answer
9
views
Google Earth Engine - Get Image with highest max Scene NDWI
By adapting code from Getting Image with highest max Scene NDVI from Image collection using Google Earth Engine I have been able to make a script that gives me the date and mean highest NDVI for each ...
1
vote
0
answers
21
views
QGIS-3 prints different QgsFeature ID compared to QGIS2 why?
in QGIS-3 QgsFeature id prints a different id compared to QGIS-2
in Q3 it prints PID "-9223372036854775808" in Q2 it's "0L", usiing same code in both
new_poly=QgsGeometry....
- 91
0
votes
0
answers
6
views
Exporting raster of a map to QGIS from GGplot in R
I used R to make density surface models of whales in GGPLOT. However, l can not work out how to get the model into a raster so i can use it in QGIS. I have been trying as below but the squares of the ...
0
votes
1
answer
8
views
Dynamically mask raster layer by features from vector layer in GeoServer
Is it possible to mask raster layer by features from vector layer in GeoServer?
I want dynamic connection, so adding a new feature to the vector layer will automatically change the raster layer mask.
...
- 1
0
votes
0
answers
6
views
How to fuse (fusion) Optical and SAR data using python? [closed]
Optical data (Sentinel 2 or Landsat 8) and SAR data (Sentinel 1)
0
votes
0
answers
16
views
In QGIS Modeler, how to merge the outputs of conditional branches of which some are performed and some are not?
I need to do a processing model that has several optional vector inputs, but that produces only one output. I have separate conditional processing branches for all inputs, but in the end I would need ...
- 1
0
votes
0
answers
5
views
Harmonizing Landsat TM, ETM+ and OLI thermal bands?
I want to calculate land surface temperature from time-series Landsat TM, ETM+ and OLI datasets in Google Earth Engine. I need to harmonize Landsat datasets from different sensors. I used this to ...
- 790
0
votes
1
answer
13
views
ArcGIS Pro Pixel Editor - Saving takes forever
I have to reclass many small parts in a classified land use raster using pixel editor. However, when I click "save" after a few edits, the saving process takes forever (hours until I force ...
- 23
0
votes
1
answer
21
views
Showing historic path of river using ArcMap
I am trying to create something similar to the image below for Molonglo River in the ACT using ArcMap with several TIF tiles I have mosaicked together but no luck thus far.
Does anyone have any ...
- 1
-1
votes
1
answer
39
views
Clip Line Layer to Polygon but retain the Lines outside the polygons
I want to clip a line layer to a polygon layer, but retain the lines outside the polygons.
Can anybody assist me in doing this please?
On the image included, the lines are in red and the polygon in ...
1
vote
1
answer
34
views
EPSG:4326 vs EPSG:3857 - Why are they aligned?
Firstly I'd like to point out that I am a very basic user and trying to get my head around a few things.
I have a KML boundary saved from Google Earth. I can then drop this boundary in to QGIS which ...
- 11
0
votes
0
answers
18
views
Getting GeoServer to batch delete features using WFS [duplicate]
I'm having some problems using Geoserver to batch delete features, It looks like the Geoserver does not respond properly when the number of deleted features is greater than 30.
The format of the ...
- 33
0
votes
0
answers
18
views
Finding Maximal lines from multiple parallel lines
I have a lot of parallel lines in a list, and I am looking for a way to get the maximal lines that include individual lines. For example, let's say I have 10 lines.
l1 = LineString(((0, 0), (8, 8)))
...
- 101
0
votes
0
answers
11
views
QField Cloud- New layers don't show on QField [closed]
So I am trying to set up a basic map with the OpenStreetMap layer, and I am just trying to add some basic point shapefiles. When I try to sync this with QField Cloud the OpenStreetMap layer shows but ...
- 1
-1
votes
0
answers
14
views
Nighttime Lights Data to CSV [closed]
I'm very new to ArcGIS and I'm using it for this project I'm doing that involves nighttime light images from https://www.ngdc.noaa.gov/eog/dmsp/downloadV4composites.html.
As of right now I just want ...
0
votes
0
answers
9
views
Using Folium.DivIcon to plot multiple LineStrings Length on 1 map
I have the following GeoDataFrame "melissa_segs" which is a result of an exploded Polygon and CRS is 'ESRI:102009'
poly_id
vertex_id
seg_length
geometry
0
1
103.0
LINESTRING (-1224668.715 ...
-1
votes
0
answers
14
views
What sources are free to the general public and allow their data to be used for potential commercial means in a Unity environment? [closed]
I am attempting to import heightmap data into Unity to create a virtual environment. This is for a VR re-creation of my university on behalf of it and this project will likely be used by admissions ...
0
votes
0
answers
8
views
URL Redirects/Masking with ArcGIS Online
I am creating a webmap that redirects users to an external site based on a field in my layer. Currently the system works by having a $baseURL + $variable + $key, but the third party wants to keep that ...
0
votes
1
answer
19
views
Geocoordinates to pixel value in GDAL?
I'm trying to read a GeoTIFF with one band which stores a value between 0 and 3 ( 255 is no maks ). My Goal is to write a little program which takes in a latitude/longitude and returns the fitting ...
- 117
0
votes
1
answer
14
views
How to add image in Mapbox with turf.js grid
I divide the map into squares with Mapbox-GL and trufjs and the grid is created.
I want to select some of these frames with the mouse and add pictures to the selected frames.
The image should be above ...
0
votes
1
answer
8
views
Updating/Setting Field on GML file not working
I'm currently attempting to add a new field to each feature in a file, however, the file is not getting changed.
I've tried using driver.Open(file_path, 1) and driver.Open(file_path, update=1), but ...
- 11
2
votes
0
answers
22
views
Relations in QGIS
I have the following relationship implemented in Postgres
I have designed the following form for QGIS in QT Designer for save project
What I can't find is how to save the many-to-many relationship ...
1
vote
1
answer
17
views
Date label on a Sentinel-2 image collection (Google Earth Engine)
I found a way to add text to the images of a collection using a package that GEE user Gena created for this purpose. I used this code as guide, in the addText function I used the property system:...
1
vote
1
answer
32
views
Merge a .gpx with a DEM
I have two files, a DEM and a .GPX. How can I mix the two files so that the .gpx is part of the DEM (in black and white), but rendering the color at an elevation 10m higher than the DEM?
The color of ...
- 77
0
votes
0
answers
19
views
Geometry error with QGIS
I create rectangles from the tool "Rectangles, ovals, diamonds" on a layer (shapefile) of type point that I created before. Because I need to create rectangle with specifics dimensions then ...
0
votes
0
answers
3
views
Errors on putting a chart for my NDVI timeseries (the error concerns the 'system: time_start'
// region of interest
var Bassin = ee.FeatureCollection('projects/ee-geomatiquetech/assets/BassinVersantOER_WGS')
Map.addLayer(Bassin);
// image landsat
var L5 = ee.ImageCollection("LANDSAT/LT05/...
- 1
0
votes
0
answers
24
views
ReadRaster returns wrong pixel value
I'm trying to read a GeoTIFF with one band which stores a value between 0 and 3 ( 255 is no maks ). I downloaded it from here :
https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/...
- 117
1
vote
1
answer
18
views
How can I activate GeoTIFF compression in QGIS 3.x gdal_translate?
I am a beginner at Python so please excuse this stupid question. I am working on a simple QGIS plug-in for saving GeoTIFFs and I want to give the user the option to switch on compression when saving ...
- 97
0
votes
0
answers
13
views
Pixel offset when exporting from GEE [closed]
https://code.earthengine.google.com/f026f46d5615915f584e83c2895b6a2c?hl=it
I am attempting to export a GEE image for further analysis in QGIS/Arc. However, I've noticed a slight offset in pixels ...
0
votes
0
answers
20
views
Get map to use ST_GEOMETRY function-based spatial index
SDE.ST_GEOMETRY — Oracle 18c — ArcMap/EGDB 10.7.1:
I have a view that returns the startpoint of lines as an ST_GEOMETRY column:
create or replace view bc_atn_startpoint_vw as (
select
objectid,
...
- 754
3
votes
0
answers
39
views
PyQGIS: moving legend with changed reference point
I am trying to create a print layout using PyQGIS. As part of that, I want to move my legend to the bottom right corner of the map, using the lower right corner of the legend as the reference point. ...
- 31
6
votes
1
answer
123
views
QGIS - Connection Lines using geometry generator between 2 layers in a relation N-1
I would like to know if there is any way to generate a connecting line between 2 points layers (blocks-points representing a watershed, concpoints-points representing the concentration location of the ...
- 414
1
vote
1
answer
11
views
Spatially merging two netCDF raster layers into one layer while using ArcMap
I tried to merge two .nc-files into one within ArcMap. There is one file containing the specific values for North America and one containing the values for South America (see the image below).
My ...
- 11
0
votes
0
answers
13
views
What do CORE_EXPORT and GUI_EXPORT keywords mean?
In some QGIS classes there is a statement CORE_EXPORT or GUI_EXPORT between class operator and class name. What does this statement mean?
Example in this part of surce code: https://api.qgis.org/api/...
- 1
-2
votes
1
answer
30
views
Seeking Python module to find volume of xyz data
I have an xyz file in the following format:
720567.698,733950.021,-4.20
720567.698,733949.021,-4.04
720567.698,733948.021,-3.86
720567.698,733947.021,-3.68
720567.698,733946.021,-3.45
720567.698,...
- 135
-2
votes
0
answers
24
views
Creation of rectangle on QGIS
I create rectangles from the tool "Rectangles, ovals, diamonds" on a layer (shapefile) of type point that I created before. When I want to leave my project I am informed of an error on some ...
0
votes
1
answer
16
views
Extracting the pixel value of a geocoordinate from a GeoTIFF [closed]
I have a simple GeoTIFF file where I want to query the pixel value of a certain geocoordinate.
I have no experience in this topic and there nearly no tutorials or whatever about this topic.
All I know ...
- 117
0
votes
0
answers
10
views
Trying to intersect a geodatabase with a line string using ogr2ogr
I would like to output the features of a geodatabase that intersect a line string using ogr2ogr.
ogr2ogr -sql "SELECT geometry, FULL_NAME FROM input WHERE ST_Intersects(ST_GeomFromText('...
- 2,090
0
votes
1
answer
24
views
Merging rasters from multiple days in loop using ArcPy
I'm using ArcGIS Pro 2.9.3, and I want to use the Mosaic to New Raster tool to merge groups of rasters. I have many days that each have multiple rasters within them. For example, I have
July3a.tif
...
- 127
-1
votes
0
answers
11
views
Calculating flood layer with HAND model in Google Earth Engine [duplicate]
I would like to create a flood layer with the HAND (height above nearest drainage) model in Google Earth Engine and I found this page (1) with a link to a GEE script (2).
(1) https://samapriya.github....
- 61
0
votes
0
answers
13
views
print layout for map bug
I want to create a map with legend and so on but when I actually press New print layout and then I add a map I have a blank (see img attached). Is anyone does know why?
enter image description here
- 399
0
votes
1
answer
11
views
How to export result of point_metrics() in lidR?
I have las files along coastal areas which include multiple flights. Usually I use both water and ground when normalizing but this data has 2 things to overcome. The first has ground at a lower level ...
- 427
1
vote
0
answers
16
views
How to remove all resources loaded from QGIS plugin?
I used the QGIS Plugin Builder to create a plugin where the main.py file imports dockwidgets and class from its own file and from other files. A button on the toolbar executes the run(self) function ...
- 493
-1
votes
1
answer
10
views
How to update a MapInfo table with chronological numbers
Is it possible to automatically update a column in a MapInfo table with chronological numbers (1, 2, 3 etc.).
*This is without taking a chronological number set from another table
