Questions tagged [python]
Python is an open source interpreted programming language used in many GIS programs.
0
votes
0answers
11 views
Method of splitting a polygon into multiple parts through a script
I need a tool that takes a polygon, usually shaped somewhat like the one below, and to have it split into even sections, going along it's gradient, then have some of them merged again to indicate the ...
1
vote
0answers
8 views
Join a CSV file to GeoJSON using ogr2ogr in a Python script?
I have a CSV which I would like to join to a GeoJSON.
I found this answer which I tried to implement but I can't get it to work just yet.
Here's an extract of my python:
join_command = ['ogr2ogr', '...
0
votes
1answer
23 views
Read shapefile with Fiona - AttributeError: 'NoneType' object has no attribute 'get'
I am trying to read in the following shapefile below with fiona:
import fiona
from shapely.geometry import shape
polygons = [shape(feature['geometry']) for feature in fiona.open("myshapefile.shp")]
...
2
votes
1answer
20 views
Normalized interpolation doesn't work for WGS84
I am trying to interpolate linestring on WGS84 coordinate system by factor 0.5.
LineString length is 427 meters (measured by different tools), so I expect to get line with length=213.5 meters. But I ...
0
votes
0answers
10 views
Calculate monthly sum of rainfall raster with python or shell? Gdal? [on hold]
I have rainfall data in raster file (.tif) every 3h for several years in a folder. Each file has the date into the name with the format: YYYYMMDD.HH.tiff
I want to calculate daily and monthly sum of ...
0
votes
0answers
11 views
Updating GeoNode metadata using pyCSW?
We deployed our geospatial data services using GeoNode 2.10, and would like to update/import the metadata for layers published on the GeoNode. Because our metadata is stored in another server and have ...
0
votes
1answer
18 views
Converting ArcGIS Polygon data to Lat/Long? [on hold]
I have downloaded some ArcGIS data from here:
ArcGIS Data
and there is an explanation of the schema here:
ArcGIS Data Documentation
How do I convert the values in the array to lat/long? i.e.
Here'...
2
votes
1answer
22 views
Re-project GeoJSON from pixel-space to lat-long in Python
I have created a GeoJSON of linestrings in pixel space using Python. However, I now need to re-project the file to match the same projections and extent of the .tiff file I wish to layer the GeoJSON ...
0
votes
0answers
8 views
Connect optimal path and optimal destination [on hold]
I have the following problem which can be solved in 2 stages: The first stage is to calculate the least cost path for transporting the produce from a pixel on the field to the edge of the road, for ...
1
vote
1answer
26 views
Python: Convert shapefile to GeoJSON whilst stripping and renaming fields
I'm writing a Python script to convert shapefiles into GeoJSONs but I would like to remove many of the fields as they are redundant and rename the ones I am retaining.
Here's an extract of where I ...
3
votes
2answers
36 views
PostGIS st_makeline extra columns in result
From a table of point data, there are some groups of points that can define a line (cross sections of a water course). 'cross_section' is the name of the table with the point data, geometrypoint the ...
0
votes
0answers
33 views
Writing data from QGIS to an Excel template with Python [on hold]
I have an Excel template and I'd like to get the information from attribute table into my template in .xls
I'm new to Python but I already know how to put data from a folder to the Excel (with ...
0
votes
0answers
26 views
What signal can be used to get the selection change on a feature?
Right now I am using:
self.iface.mapCanvas().selectionChanged.connect(FunctionThatReactsToTheSignal)
But this one sends two signals, one for the deselection of the previous feature and one for te ...
1
vote
0answers
20 views
Hide columns in QgsAttributeTableView with Python
I use this code to initialize QgsAttributeTableView and hide some columns in it in my custom widget:
def __init__(self, layer, canvas, hidden_columns, cache_size=5000, parent=None):
"""...
0
votes
1answer
22 views
arcpy.SelectLayerByAttribute_management reference a field and a variable
I have tried every which way but the right way. I can't seem to get the quotes in the right spot. I have a float field called speeds and I want to compare it to a float variable I am calling ...
1
vote
0answers
60 views
What is the correct way to delete temporal files from geoprocess tools in ArcGIS, ArcPy?
I found that geoprocessing tools like arcpy.gp.SegmentMeanShift makes a lot of heavy temporal files (script is shown below) that keeps lock while the script shell its open, so you can't delete them, ...
3
votes
1answer
45 views
Error using rasterio's sample method
I'm using rasterio's sample function to get values from a (single-layer) raster based on a list of x,y locations:
for val in myraster.sample(locations):
print(val)
This works fine for the first ...
1
vote
1answer
27 views
GeoPandas does not identify points inside polygon
I am trying to intersect some points with a polygon in GeoPandas.
First I create a Point GeoDataFrame from a text file.
import geopandas as gp
import numpy as np
import pandas as pd
from shapely....
0
votes
0answers
14 views
How to populate an item's tables list for a ArcGIS API for Python Map Service Item?
I am trying to obtain a specific table from a Map Service item, however the table list is empty. The layers list correctly reports back 5 layers.
My code snippet below:
search_result = gis....
2
votes
2answers
30 views
Programmatically determining version of ArcGIS API for Python?
I would like to obtain the version of ArcGIS API for Python for logging/diagnostic purposes.
Is there a way to determine this before a connection is made?
I know that once I have the GIS object, I ...
2
votes
1answer
28 views
How to get the source name of a feature layer
I have feature layers that have a different name in the TOC then that they do in the GDB. I cannot change either of these and I need the name of the feature class from the GDB in order to make my ...
0
votes
0answers
26 views
Changing Color of Border After Clipping using Google Earth Engine?
I require nighttime satellite imagery over a particular geometry, clipped by Census Tract.
I have uploaded shapefiles into EE. I am going to loop through particular shapes and dates to export images ...
2
votes
1answer
50 views
Getting spatially referenced tiles from WMTS
I have been able to download tiles from a WMTS request in .tif format using owslib in standalone python:
from owslib.wmts import WebMapTileService
wmts = WebMapTileService('wmts_url')
img = wmts....
0
votes
1answer
23 views
Count number of pixels from .msk in Python to derive study area size
Apologies I am totally new to GIS in Python.
I am trying to find out the total area of the Barents Sea mask the NSIDC use to calculate their products and therefore I need to know how many pixels the ...
-2
votes
0answers
21 views
Polygons vector shapefile conversion to xyz format using Python [on hold]
I have to convert a vector multipolygons shapefile to an xyz file where x and y are the lon and lat of points in the vector file extent, and z is equal to 0 for a point outside polygons, and equals 1 ...
0
votes
0answers
10 views
How to join the Least Cost Path with Optimal Destination?
I have the following problem which can be solved in 2 stages:
The first stage is to calculate the least cost path for transporting the produce from a pixel on the field to the edge of the road, for ...
0
votes
0answers
37 views
Converting NetCDF dataset array to GeoTiff using rasterio Python
I have read a NetCDF file using the netCDF4 library and then read one of its datasets ("Evapotranspiration") into a variable (variable contains array) using the following code. Subsequently now I am ...
0
votes
0answers
18 views
Python matplotlib not available error with QGIS 3.6 Noosa despite upgrading Python on Mac
While generating contours in QGIS 3.6 Noosa on Mac I get an error saying "python matplotlib not available". I've downloaded the latest Python version but the problem persists.
1
vote
0answers
26 views
Python rasterio for saving GeoTIFF files and read in ArcGIS or QGIS
After following the steps in the tutorial of the Planet website (https://developers.planet.com/tutorials/convert-planetscope-imagery-from-radiance-to-reflectance/), I want to save each individual band ...
0
votes
0answers
24 views
.xyz file(coordinate files) in python [closed]
I have got a .xyz file (coordinate file which contains coordinates of atoms). Is there a way to convert it to .txt file in python?
OR
How can I read and write on a .xyz files in python ?
1
vote
1answer
18 views
Parsing an input parameter to gdal:rastercalculator formula in QGIS 3.6 Python script
For training purposes I'm writing a QGIS 3.6 Python script. The script takes as inputs a raster layer and band, and three float numbers (refmult, refadd, sunel) and computes a simple formula:
((layer@...
1
vote
1answer
65 views
Drawing graticule with GDAL/OGR
I'm trying to generate a graticule with user-defined range of latitude, longitude, and interval; however, my code only displays one line of latitude and one line of longitude when loading it in QGIS. ...
0
votes
0answers
19 views
Error with Script Publishing Service from MXD with UNC Paths
I have script that attempts to publish a service which consists of a single tiff.
I am using boilerplate ESRI code for this one:
# initialize
imagery_date = 'some date'
folder_name = 'name of ...
0
votes
0answers
26 views
Python rasterio save GeoTIFF files
After following the steps in the tutorial of the Planet website (https://developers.planet.com/tutorials/convert-planetscope-imagery-from-radiance-to-reflectance/), I want to save each individual band ...
2
votes
0answers
44 views
OpenCV Remap image from rectified image coordinates
I have orthorectified a drone image using ground control points. This results in a (4096 x 2160) array of recified X coordinates and a (4096 x 2160) array of Y coordinates. I want to remap the ...
0
votes
0answers
27 views
How convert OSM relation to GeoJSON -based all kind of relation member roles
I just want to convert OSM data to GeoJSON where it is pretty simple with node and way tags of OSM data, but relation which is giving complex can't find the logic to convert OSM relation to GeoJSON ...
0
votes
1answer
34 views
Replicate QGIS operations in PyQGIS [closed]
What is the best practice for calling QGIS/SAGA/GRASS algorithms from pure Python e.g. the command prompt or in PyCharm? I know that from QGIS -> Processing -> History, I can retrieve the code and ...
1
vote
0answers
25 views
Blank MapCanvas Window [closed]
I am constructing a GUI using PyQT4 and QGis. Rigth now I can open the MapCanvas whith same buttons of Zoom In/Out using this code:
from qgis.gui import *
from qgis.core import *
from qgis.PyQt.QtGui ...
1
vote
1answer
83 views
List of lat-long, need values in a raster
Apologies in advance as I am not a GIS specialist by any means. I have a set of 1 million points and I'm trying to find their values in a geotiff raster. I've tried various versions of this answer ...
1
vote
1answer
23 views
How do I open / move the focus to a layout in ArcGIS Pro using Python?
I have an ArcGIS Pro project which contains multiple layouts. I've got a Python toolbox with a script which, among other things, chooses which of the layouts is appropriate for a specific map. At ...
2
votes
0answers
43 views
Files locked after running a Python script
I can run a Python script that uses qgsVectorLayer, qgsRasterLayer and many functions like processing:runalg("qgis.difference"......) and os.popen("gdalwarp -q -cutline.......)
but if I want to run it ...
-1
votes
0answers
22 views
QGIS 3.4 using pygis for deleting columns v2
I have tried now to implement the code from BERA into the code from J. Monticolo. in order to get a script that is able to delete a set of columns from an attribute table. Previos Post.
But I am ...
0
votes
1answer
25 views
Create mean raster stack from raster stack
I am trying to create a mean stack image(1 panchromatic layer) from a stacked tiff image(13 panchromatic layers). How do i go about doing this?
My code:
from osgeo import gdal
import numpy as np
#...
1
vote
0answers
17 views
Extracting certain landcover type in CONUS with Google Earth Engine?
I am new to Google Earth Engine and I would like to export the pixels with landcover type of deciduous broadleaf forest (MCD12Q1 with LC_Type1 equals to 4) in google earth engine. And the following is ...
0
votes
2answers
119 views
Testing if os.path.exists with ArcPy?
I am having trouble getting the os.path.exists to recognize that a file exists. I keep getting "File does not exist". I reduced the code to the absolute necessary to address my question. I believe ...
0
votes
1answer
30 views
Keep getting “no such file or directory” DriverError in GeoPandas [closed]
I am new to using GeoPandas and Jupyter Notebook. I am able to define a name, let's say regions as
regions = gpd.read_file('FilePathHere.shp')
Then I am able to plot the shapefile.
When I start a ...
1
vote
1answer
21 views
Is it possible to print a map in PyQgis3 of a database table without rendering the layer in the project gui?
There is a way to print a map using pyqgis3 without rendering the vector layer in the project interface? (by giving just the connection to the table, the map extent and the style )
-1
votes
0answers
39 views
How to georeference image in QGIS using Python code? [closed]
I stitched images from my drone and I have longitude and latitude of centre of image. Also I know that drone was taking images from 50m height and focal length of camera is 35mm. Image is oriented to ...
2
votes
0answers
51 views
Rasterizing polygon grid in Python (geopandas & rasterio)
I am trying to rasterize a custom polygon grid with one or more columns. Preferably I'd like to create multiband rasters from multiple GeoDataFrame columns (in polygon grid), but I have got stuck even ...
-1
votes
1answer
34 views
Classify polygons with Random Forest on Python
I have a segmentation shapefile made with e-cognition containing many polygons of which a part classified for the train file. I would like to classify them by applying labels (e.g. water, vegetation, ...
