Python is an open source interpreted programming language used in many GIS programs.

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4
votes
1answer
94 views

Clip raster by mask layer returns error “wrong number of parameters”

Using Python for QGis 2.14 Essen i try to clip a raster by a Polygon, as indicated here: http://docs.qgis.org/2.6/de/docs/user_manual/processing_algs/gdalogr/gdal_extraction/cliprasterbymasklayer.html ...
1
vote
2answers
67 views

Select by attributes on PYQGIS 2.14 Essen

I'm trying to make a selection by attribute with python on QGIS Essen, but it looks like I am making a mistake on the script and I can not find it. Can somebody tell me what I have made wrong, or how ...
1
vote
0answers
48 views

Getting started with GeoJSON using Python [closed]

I am a GIS analyst who knows ArcGIS and Python pretty well and have used QGIS. I am attempting to learn about GeoJSON and web-mapping. I am looking for suggestions on tutorials explaining GeoJSON, and ...
2
votes
1answer
60 views

Drivers of Fiona

What drivers does the python package fiona have? When I check the manual it says [...] and the possible formats are enumerated in the fiona.drivers list. However, when I type in python from fiona ...
3
votes
2answers
124 views

GDAL/OGR ogr.Layer.Intersection fails when producing mixed geometry results

I am trying to intersect layers using the ogr.Layer.Intersection method, in Python. This works fine for pairs of polygons, but I have found intersecting two linestring layers containing matching ...
1
vote
0answers
25 views

QGIS cannot load macro function?

This has me stumped. For some reason, I can no longer run a function from a project macro even though macros are enabled (from Settings > Options > General > Enable macros > Always). Just ...
0
votes
0answers
42 views

How to georeference *.tiff to a given feature geometry automatically?

I´ve got the task to georeference an tiff image to the referencing polygon footprint (Polygon). I have found a lot of ways to do get the footprint from a raster but I could not find a way to use ...
0
votes
0answers
27 views

OGR WFS - GetNextFeature() - cannot parse - element arg attribute name had invalid value TYPENAMES

I am new to Python and OGR, and i try to follow advices given by Gene in ouvrir un WFS - debutant, but it fails... from osgeo import ogr driver = ogr.GetDriverByName('WFS') wfs_ds = driver.Open("...
8
votes
3answers
209 views

Increase Tiles Caching Speed (TileStache)

I am serving vector tiles using TileStache, I have everything set up like I want. My data is stored in Postgres and I am using the VecTiles provider to serve GeoJSON tiles. I want to cache all my ...
2
votes
0answers
33 views

Reading raster attribute table using gdal in python

Is there a GDAL function that can read in a raster attribute table? Something functionally similar to this function in pygeoprocessing: pygeoprocessing.geoprocessing.get_rat_as_dictionary_uri(...
1
vote
3answers
129 views

Multiple python import from feature class into feature dataset in geodatabase

Is it possible to create a python script to import shapefiles/feature classes, from different sources into specific feature datasets in geodatabase, but in one script? I managed to write the script ...
0
votes
1answer
124 views

How do I convert a DEM GeoTIFF to Contour Shapefile

I have a digital elevation model as a GeoTIFF and I'm looking to generate a Shapefile of contours with 5m bands on the command line. Is this possible? Ideally using GDAL and Python.
3
votes
1answer
120 views

Memory error in python when reclassifying array

I have a .tif that I read into an array (call it tifArray), and I would like to classify the array based on set of conditions: Where 1200 <= tifArray <= 4000, outputArray = 1 Where tifArray &...
4
votes
1answer
91 views

Can't delete features from layer using QGIS' Python API

I've only recently started using QGIS and it's Python API. Currently I've loaded two OpenStreetMap datasets. I would like to remove lines with from the second set where the name is already present in ...
0
votes
1answer
94 views

numpy.unique: ValueError: all the input arrays must have same number of dimensions

I'm trying to get the unique values of an array but am getting an error that doesn't make any sense. Here is my pseudo code: import numpy as np import gdal # I have a .tif file, call it inputRaster:...
1
vote
0answers
74 views

QGIS 2.14.1 Processing Plug-In does not work anymore (Python error)

I did not change anything and started QGIS 2.14.1 today and was greeted with the following error message. So the Processing tab is missing and I cannot activate it. The error: 2016-04-26T17:58:43 1 ...
2
votes
2answers
52 views

Sort Column and Sequentially Number Separate Column

I am trying to sort (alphabetize City) a column, and sequentially number a separate column for the purpose of labeling and creating a map key. What is the best way to do this?
0
votes
2answers
75 views

How to connect push button in dock widget form?

Following this tutorial as a guide, I created a plugin using the Plugin Builder with the dock widget form. I am now trying to connect a pushButton to a function. The following is a snippet of code: ...
2
votes
0answers
44 views

How to use ST_VoronojDiagram for points that are almost aligned?

I am trying to use the spatialite ST_VoronojDiagram function on a table containing four 4 points that are almost aligned: (1.01 2.02, 2.02 3.03, 10.01 10.02, 11.01 11.02). I wrote the following script ...
-1
votes
1answer
47 views

Listing Points Within Polygon for Hadoop? [closed]

I am very familiar with a point in polygon analysis but instead of counting how many points are within each polygon. Does anyone know how to list the points within the polygon and add a field that ...
1
vote
1answer
118 views

Writing result of PyQGIS to shapefile

I try to perform some zonal statistics on a shape- and rasterfile and write the output to a completely new shapefile! import sys # where is the module sys.path.append("/Applications/QGIS.app/Contents/...
1
vote
2answers
48 views

Arcpy fail to loop between files in different directories

I want to perform a loop of intersections between different files in different directories. Here is my code: Intersects = ['Name1','Name2','Name3','Name4','Name5'] #Names of my files arcpy.env....
0
votes
0answers
65 views

Layer stacking many images using Python and Erdas Imagine Spatial Modeler

I have downloaded huge amounts of Sentinel 2 data to cover a large area of the Himalayas and need to layer stack each tile. I have decided to use Python to do this using the LayerStack tool from Erdas ...
1
vote
1answer
150 views

Assign a point to polygon using pandas and shapely

I have a series of Easting and Northing coordinates in pandas dataframe along with other columns of information. I know the coordinates fall within and administrative area and want to match the ...
0
votes
1answer
30 views

Empty file after saving…? [closed]

Code below is working, but after opening - there are No features in shp file. What can be a problem? import osgeo, os from osgeo import ogr, gdal shpFile = r'C:\Users\ReBurns.shp' driver = ogr....
1
vote
2answers
117 views

Scripting (Python) Feature Class content into Shapefiles following an UTM data structure

Consider a Feature Class and two of its fields are "UTM_grid" and the "OID". Scripting with python 2.7 for ArcGIS 10.3. "UTM_grid" field contains the geographic info (e.g. B1SD40B) and was broken ...
4
votes
0answers
54 views

Issues updating field values programmatically for particular field data type on 64bit Windows computer using QGIS 2.8.7

I have an issue with a plugin for QGIS 2.8 I'm developing when using it on a Windows 64bit machine (as opposed to 32bit). I am trying to update values in a particular field in my plugin, and the ...
3
votes
0answers
43 views

Translating ArcGIS field calculator python expressions in to QGIS field calculator python expression?

I'm transitioning to QGIS from ArcGIS. I'm having trouble getting my python field calculator expressions to work in the QGIS advanced python field calculator. Here is a screenshot of the working ...
3
votes
1answer
47 views

PostGIS: floating point representation problem with ST_AsText

I have a table with geometries, all with about 13 digits of accuracy. While trying to represent them with ST_AsText though, most vertices come out in decimal notation, but some come out in scientific ...
1
vote
1answer
111 views

Remove/subset raster bands in Python GDAL

I'm trying to remove bands from a raster I have. Basically I just want the first band as a new GeoTIFF file. Here is my code so far: #!/usr/local/bin/python from osgeo import gdal # Load my GeoTIFF ...
3
votes
1answer
37 views

Building a tool to both geocode and do topology check on the geocoded point (ArcGIS)

Never built a tool in ArcGIS. Would someone tell me if it's feasible to create a single tool (preferably using Python) which: Geocodes an address Checks to see if geocoded point falls within a ...
1
vote
1answer
65 views

Why does joining all layers in a group not work?

I am attempting to re-join all layers within a group to another layer ("Main.shp") outside of this group. The idea is for users to change values in one of the group's layers. As these layers are ...
0
votes
1answer
57 views

Python-ArcObjects mxDocument Stand Alone

if I need to work with classes MxDocument with the MapDocument that I have selected to work , for example style gallery, How can I instantiate ? InitStandalone() pMapDoc = CreateObject(esriCarto....
3
votes
2answers
79 views

Find points that intersect a user-defined polygon in GDAL

I'm trying to do something that I don't know is possible in GDAL/Python. I have a list, L, of pre-defined lat/long points that make up a uniform grid. A user will send me a set of points that make ...
2
votes
0answers
39 views

QGIS Function Editor/ Python question

I'm currently using the layer_property(layerName,'source') to produce a list of copyright statements for the Print Composer by putting that in an if() statement. However, that isn't very flexible as ...
4
votes
2answers
67 views

How to get layers in x number of subgroups?

I have a project which has dozens of groups and subgroups. E.g.: Main_Group > Sub_Group_1 > Sub_Group_1A > Layer_1A > Layer_2A How can I access ...
1
vote
0answers
44 views

Eclipse PyDev has quit recognizing QGIS objects

I followed the instructions for setting up Eclipse with PyDev to start creating QGIS plug ins found here: http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/ide_debugging.html after doing ...
2
votes
1answer
121 views

Get intersection of circles shapely

I have a List of Points which I transform to circles. Code from here circles = [Point(random.random(), random.random()).buffer(random.random() * 0.1) for i in range(3)] I want to know which circles ...
2
votes
0answers
56 views

Deployment of optical fiber QGIS Python

The subject that I’m working on is the deployment of optical fiber . I have a shapefile which represents a country containing homes. And I have another shapefile representing an infrastructure plan of ...
5
votes
1answer
76 views

Getting pixel values at single point using rasterio

To get a single pixel value at a point in a raster using rasterio, there is an example here: https://github.com/mapbox/rasterio/pull/275 However, is there a direct API within rasterio (and not the ...
4
votes
2answers
228 views

How to render layer into png in a standalone application?

I would like to use standalone appliction to apply .qml style to a layer and use QgsMapRenderer() to save it as image on a hard disk. The are a lot of questions like mine at this site and it seems ...
3
votes
2answers
62 views

Label and symbol with condition in layer properties under style tab

I have forest areas. I want to put tree.svg with condition. Layer properties-> style-> background -> shape ->svg Something like this: if (myfield<1300 , then show, C:/PROGRA~1/...
0
votes
2answers
51 views

Trouble getting shapely to run

I downloaded the GDAL complete Framework von Kyngchaos which also includes the GEOS Framework and shapely for python. I can import shapely without a problem, but when I try to perform some "geo ...
3
votes
3answers
62 views

How to get appropriate CRS for a position specified in lat/lon coordinates?

I have a set of city networks whose coordinates are specified in lat/lons. I wish to run an algorithm on each network that treats them as a planar graph. I'm using python and can use pyproj to project ...
0
votes
2answers
85 views

Casting between PostGIS types in GeoAlchemy

I'm working with OpenStreetMap data, and loading it into a PostGIS database using osm2pgsql. The issue that I am currently dealing with is that osm2pgsql stores the shape as a geometry type. I'm ...
0
votes
1answer
71 views

Why can't I run .tif file with GDAL?

I am trying to extract data from a geotiff file in the Ubuntu terminal. My professor used the command "gdal NDVI.tif" and was able to write the data to a text file. When I use that command, I get the ...
1
vote
0answers
31 views

Python GDAL open dataset in PostGIS with quotations

Error trying to use gdal to open a dataset in PostGIS with the following code: ds = gdal.Open("PG: dbname=nyc host=localhost user=postgres password=mypassword port=5432 mode=2 schema=public column=...
1
vote
1answer
66 views

How to pythonically set a symbol as an ascii character (Font Marker) in QGIS

I need to set a point on a map as an ASCII symbol with python. I'd like to do this in a rule based renderer. something like: rule.setSymbolAsFontMarker("✫") So I'd have something like this in my ...
2
votes
0answers
37 views

Writing 3 channels to 8-bit TIF in Python using gdal

I have some Python code to write 3 channels to file. Here, channels is an array of 3 numpy 2D-arrays (RGB), outfile is the filename, and rows and cols are the image dimensions. def save_tiff(channels,...
1
vote
0answers
38 views

Using “Ruled Based Render” to display labels without the marker with python in QGIS

I'm writing a script to load and manipulate some shapefiles. Unlike my previous question I now need to display labels only on certain zoom levels. My usual result is that the previous formatting gets ...