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

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python crop aerial image

How can i crop an area from an aerial image knowing the latitude and longitude of the image's corners and also the cropped section? I have a LiDAR scan and i and want to crop an image overlay to fit ...
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1answer
51 views

Getting error 'exceptions.NameError' in Python script?

I'm getting <type 'exceptions.NameError'>: name 'B' is not defined when I run this script. Why is my 'B' not defined and is it a syntax error? For clarification, I am trying to get the code to ...
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1answer
31 views

How to plot Storm Prediction Center (SPC) Shapefile using python

I am trying to make a plot of the SPC's thunderstorm outlook using Python. I have downloaded the shapefile from this website http://www.spc.noaa.gov/products/outlook/day1otlk.html. Then I use this ...
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1answer
34 views

Error using 'Join attributes by location' via Python

Trying to run a simple script using qgis:joinbylocation but getting either errors or it's not processing correctly. I don't want to take a summary of the attributes, just the attributes of the first ...
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1answer
819 views

Multiline VBScript Label Expressions in Arcpy

I am able to set simple label expressions, but when I try to set multiline expressions (which all VBScript expressions are) it does not get copied into the expression box properly. I have tried using ...
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1answer
30 views

Issue using Matplotlib in QGIS

I am developing a QGIS-plugin and for graphing I want to use matplotlib, like many other QGIS -plugins. This worked fine under linux, but under windows with QGIS2.4 I am experiencing problems. I ...
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3answers
31 views

FeatureClassToFeatureClass_conversion in ArcGis 10.1

I have many > 60 .dwg files I want to convert just the polyline parts of these and have put together a list of python commands using excel to get something like this: However when I try running ...
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1answer
24 views

How to determine bounding box of current qgis 'map canvas extent' from the python console

I've asked a similar question here: How to quickly calculate bounding box coordinates of a selected polygon with qgis ...regarding a quick way to determine the bounding box of a given layer. Is ...
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14 views

QGIS + python, Attribute index 0 out of bounds [0;0] when adding a feature to a PostGIS layer (view)

I have a plugin which adds features to a particular PostGIS vector layer using the code below feat = QgsFeature() feat.setGeometry(qgsgeometry) layer.dataProvider().addFeatures([feat]) For one user ...
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1answer
34 views

Arcpy Subtracting rasters error - TypeError: 'unicode' object is not callable

I have a script which subtracts 2 versions of the same raster from each other (one newer than the other) and then extracts the additions & deletions that have happened. I created a simple test ...
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3answers
38 views

ArcGIS arcpy code fails in Toolbox mode

This code executes correctly in Python window but fails with ERROR 000732: Input Table: Dataset JHJ does not exist or is not supported # Import ArcPy and other required modules import arcpy ...
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1answer
127 views

Raster extent, just clipped by geomtery, slightly differs from a given geometry

The raster using arcgis geoprocessing is cliped with a feature, reading it's geometry and as a result, rasters extent slightly differs. Extent of geom: str(row.shape.extent) '570600,537958652 ...
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3answers
74 views

How to Build a graph from a map

I spent days looking in all questions here and trying tutorials. I need to build a graph for a region (It will be my input in simulation) I downloaded Postgresql and Postgis and osm2pgsql. Now i can ...
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1answer
5k views

Thiessen Polygon delineation within a Feature

I am trying to create Thiessen (Voronoi) polygons, based on points within a defined shapefile extent. The output should be inclusive to the feature. The output I receive now is the rectangular area ...
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0answers
52 views

I cannot use Gdal Python but Gdal binary, how to fix?

**UPDATE: I can use GDAL with Python now by copy file from Gdal 1.11 compiled folder to Python package folder. But the problem with GDAL binary and GDAL library that they cannot read the HDF5 file. ...
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2answers
157 views

Issue while running grass from subprocess

I have a map based web application using geodjango. I needed to display the crime hotspots within a selected polygon area. I found that v.kernel is very good for generating heatmaps/hotspots. So in my ...
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1answer
117 views

How to save after using fet.setFeatureId in pyQGIS?

By using the following code, I want to change the id of the line when saving the line. But the setFeatureId command, gives a false when doing the commitChanges(). Any idea how to change the id? vl = ...
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0answers
71 views

GIS projects with a raspberry pi [closed]

Does anyone know of a project using a raspberry pi and gis that would work for a research project for a computer science major? I am looking to do a research project involving a raspberry pi and ...
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1answer
60 views

forLoop & joinField & different names

I have a folder with an output (shapefiles) from an iteration. On this output, I want to perform a join between two attributetables. So far so good. Here comes the tricky part. There are different ...
3
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1answer
65 views

Dynamic title in ArcMap

How can I have a dynamic title of the map, which changes depending on the layer chosen? Is this doable? It would save a lot of time and iterations since I should be producing several maps. To ...
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2answers
148 views

How to bulk print maps using ArcGIS or QGIS?

I have a polygon layer that I would like to print images or PDFs from in bulk as there are a large number of them. Rather than having to manually scroll and print each individual'site' in the print ...
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1answer
40 views

How to get a Layer as ILayer (ArcObjects)

I had asked this question previously which I think will work. But as I am new to this, I can't figure out how to get a Layer as an ILayer object to pass to the method that's in my previous questions ...
2
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1answer
37 views

How to transform JSON with field x,y to gdb in fme

I have JSON file with x,y field. I wonder how to transform geoemtry to gdb? Example of json: [ { "OBJECTID": "1", "x": "15", "y": "21" }, { "OBJECTID": "2", "x": "16", ...
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27 views

Does somebody has a Python script for a Multiple Flow Algorithm?

I´m looking for for a python script for a multiple flow algorithm assigning flow to all lower cells from one central cell. This algorithm is part of the r.terraflow and would need it to start at a ...
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1answer
327 views

Converting Tab to Shp Using OGR2OGR with Python on linux

First i downloaded http://svn.osgeo.org/gdal/trunk/gdal/swig/python/samples/ogr2ogr.py and i am importing this. How can i get ogr2ogr to run in my script? nothing seems to be working and i not sure ...
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2answers
246 views

Checking current user privileges for an SDE dataset with Python/arcpy

I am managing data distribution via an ArcSDE Oracle gdb to a number of users (schemas?), each of which can only have read only access to datasets they have requested access to, and have then been ...
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2answers
372 views

Using reader Feature Type Name as Writer Feature Type Name in FME

I've search and searched for a way to do this, but no method seems to work. Basically I want to use the input feature class name (feature type in FME) as the output name. This normally works, ...
4
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1answer
148 views

Why is matplotlib installed with ArcGIS?

Today I upgraded to ArcGIS Desktop 10.2.2 as well as the 64-bit background processing tool and noticed that both numpy and matplotlib were installed with Python. In fact, in the "What's New?" section ...
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1answer
24 views

Arcgis, Convert analyse result in numeric value

I have a problem that seems really simple but blocking me... in Arcgis i have script python where i want to extract the resolution of a raster and use this result like numeric value for use in a ...
0
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1answer
21 views

ArcMap 10.2 Sum Acreage for matching areas in another field; ultimately use ModelBuilder?

First off, what I'm attempting to accomplish is to sum the acreage of matching "WUNAME" and populate the "WU_Acre" I've tried to highlight the fields as shown and use the field calculator SUM(Acreage) ...
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2answers
1k views

Using newline/page break tag in ArcGIS Desktop Text_Element in arcpy.mapping? [duplicate]

I want to update a Text_Element with a newline or page break using ArcGIS Desktop 10.0. Does anyone know the tag or syntax?
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80 views

MultiLineString to separate individual lines using Python with GDAL/OGR, Fiona, Shapely

There are lots of MultiLineString features in a polyline shapefile. The problem is to split these lines into separate individual lines. There is a similar question with PostGIS, but I need to code in ...
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2answers
135 views

Changing default parser in ArcGIS Field Calculator to Python?

Is there a way to change the default parser in the Field Calculator to Python? So annoying to always change now that I'm trying to move away from using VBScript... I'm using ArcGIS 10.1 for ...
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1answer
34 views

Python Toolbox (.pyt) Tool Output Layer Name

How can I manipulate the TOC display name of my output parameters when using a Python toolbox (.pyt) Tool class. I tried adding a symbology layer, however this has no affect on the TOC name. Is it ...
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2answers
91 views

GeoAlchemy pg_function.geojson cannot be decoded with json.loads

I asked this quesiton over on StackOverflow and thought it might make more sense to post it here given it's GIS nature. Given this function: features being a list of SQLAlchemy objects template ...
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1answer
422 views

Scipy: Convert RGB TIFF to grayscale TIFF and output it on Matplotlib

I want to manipulate RGB bands in a TIFF file and output the grayscale map on matplotlib. So far I have this code, but I couldn't get it on grayscale: import scipy as N import gdal import sys import ...
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1answer
55 views

Possible to run “Merge shapefiles to one” algorithm from Python script?

Developing a python script in QGIS 2.2, I can run algorithms from the Processing plugin fine such as those from QGIS geoalgorithms and SAGA. Can you do the same for the algorithm "Merge shapefiles to ...
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1answer
312 views

How to re-project the EASE (Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?

I have nc files ,here is one file https://echange-fichiers.inra.fr/get?k=LUfqiyO1Dl7az5bihnS. from the metadata ,the projection is cylindrical and the resolution is 25 km: ...
2
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1answer
257 views

View HTML field data with QT4 browers as a QGIS Run Feature Action Tool

I've successfully populated a sqlite table with an HTML-encoded-table as a field attribute, and so there is literally a Table within a single field value in sqlite, for each record. This is going to ...
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1answer
107 views

visualize bounding box to a polygon

I try to make plugin in QGIS that compare 2 bounding box data, ex: (-32.61442167739459, -32.017601026186576, 13.015663782506067, 13.428145228091406) and (-38.6102467739459, -38.017601026186576, ...
3
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2answers
106 views

Memory and Processing Efficient Approach to Read a Timeseries in Python

I am trying to store a timeseries of high resolution raster images containing NDVI values into a dictionary for calculations. I am curious as to which approach may the most efficient when loading ...
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3answers
123 views

Applying rotation before FeatureToRaster_conversion?

I am converting polygon shapefiles to rasters. With arcpy I am using the function FeatureToRaster_conversion. gp.FeatureToRaster_conversion(InFeatures, InField, OutRaster, InCellSize) This function ...
4
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2answers
628 views

Is it possible to route shapefiles using python and without ArcGIS, QGIS, or Pgrouting?

The question is pretty much in the title. Is there a way to route through a road line shapefile using python and some library without having to resort to converting the data into PostGIS/pgrouting or ...
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3answers
133 views

Setting symbol descriptions of ArcMap layout legends from table?

ArcMap has the ability to show an extended description for each item in the symbol list. How can I populate that property from a table? The goal is to avoid having to edit each symbol one by one in ...
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0answers
28 views

Why does python reads only the no data value from GeoTiff file?

I had a number of tiff files with a country's map. They had different rows, columns or different projections etc. I needed to make them with same projection, spatial resolution and same number of rows ...
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0answers
31 views

How to programmatically add a new plugin repository in QGIS?

How can I add the name of a repository and URL to the third-party plugin repository using python in QGIS 2.01?
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3answers
908 views

How to connect the selectionChanged signal with pyqt?

Hi I am developing a plugin for Qgis in python, I need to connect the sselectionChanged signal emitted when a feature of the layer is selected, I could not find any examples on internet, here is what ...
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0answers
19 views

Error when providing “Python init function” from Python script in QGis

Problem I am using QGis and Python scripting to programmatically set a layer's edit form and "Python init function". It appears that the Python init function is called correctly in one situation ...
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1answer
51 views

Import error when utilizing QGIS's Python Init function

Based on the answer to Referencing Qt UIs external to plugin with python. I'm trying to utilize the "Layer Properties / Fields / Python Init function" to execute a file (test_file.py) that is located ...
3
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1answer
289 views

How to Populate new field using expression containing MAX value from another field in ArcGIS attribute table using field calculator?

I've got one field X with 10 numerical attributes (float/double). I've created a new field Y (also float/double) which I need to populate with the percentage of each record/attribute (in each of the ...