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

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1answer
110 views

Processing algorithm fails from Python script

I'm trying to write a Python script performing a geoalgorithm. What is surprising me is the following: I first test the algorithm by QGIS (2.8) interface. In my case, the GRASS interpolator ...
2
votes
1answer
84 views

Looking to find (or build) a particular Python geoprocessing tool

So here is my situation: There is a large area (a wildlife refuge) of nearly 200,00 acres that we have loads of spatial data for, from habitat management projects from the past several years. My boss ...
2
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1answer
228 views

Python: how to set a different output folder

I want to transform some vectors to rasters in my folder but I have difficulties setting the output folder. The following code only allows me to output to the original database. I hope to output all ...
2
votes
1answer
84 views

Landsat Surface Reflectancce product Python packages

I have to work with numerous Landsat surface reflectance product that I downloaded from http://landsat.usgs.gov/CDR_LSR.php. The product comes with a QA data with information on clouds and shadows ...
2
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1answer
264 views

How to create a plugin GUI for QGIS 2.8.2?

I create a pluging with the pluging builder in Qgis 2.8.2. I went to the folder of my pluging : C:\OSGeo4W64\apps\qgis\python\plugins\yu in order to visualize al the files that the pluging builder ...
2
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1answer
2k views

Interpolation grid for scattered data having (latitude, longitude) coordinates

I've got some scattered data in the form of (latitude, longitude, someParameterValue). I'm using inverse distance weighting interpolation method to interpolate them in a rectangular grid of pixels. ...
2
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2answers
389 views

How to create a line between a point and nearest neighbour using python (template included)

I have 2 shapefiles - one is a series of points, the other is a polyline. I want to draw a straight line between each point to the nearest point on the polyline. This question has already been asked ...
2
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1answer
48 views

What's the syntax to skip optional saga:catchmentareaparallel parameters?

In PyQGis, I want to use saga:catchmentareaparallel algorithm, in the parameters there is an optional arguments, and I don't want to use them, what is the value should i put on the argument? i try to ...
2
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1answer
262 views

Identifying Left and Right Mouse Button Clicks in PyQgis application

I am relatively new to PyQt. I am trying create a custom plugin for Qgis which enables the user to select some features by drawing polygon on the canvas using mouse clicks and then performs ...
2
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1answer
258 views

Unable to compile using make test in Linux

While trying to compile my test plugin I encounter this error, for the moment I can't figure out why, last week I had some issues on windows but eventually solved them via OSGeo Shell but this time ...
2
votes
1answer
146 views

Setting Two Definition Queries as Parameters in Python Script tool causes: RuntimeError: LayerObject: Set attribute definitionQuery does not exist

I created a script that adds definition queries to every layer in an mxd depending on the layer name. This worked fine as a stand alone script, but when I try to use it as a script tool with ...
2
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2answers
456 views

How to get path for layers listed in a combobox?

I want to get the path of a layer in my plugin, in the console it works fine but in my plugin it gives me the error AttributeError: 'NoneType' object has no attribute 'dataProvider' def run(self): ...
2
votes
1answer
239 views

How to use the math tool (“times”) in ArcGIS modelbuilder to multiply two raster sets while using an iterator?

I have two sets of rasters (in the same gdb), representing "loss" and "forestmask". I would like to multiply each forestmask raster (value 1 = forest) with its corresponding loss raster (value ...
2
votes
1answer
159 views

Using a for loop to execute a query in arcpy

I'm trying to provide the breakdown of fire detection for an area by sorting of confidence levels. The dataset has 12 files (one for each month in a year) with fire records which all have a column ...
2
votes
1answer
170 views

use gdal python bindings from the QGIS folder in a custom script

I have QGIS installed (on Windows) and can import this line from the QGIS Python console: from osgeo import gdal When I try the import in a python file it doesn't work Traceback (most recent call ...
2
votes
1answer
65 views

Arcpy if statement to act on layers at the top level of hierarchy

I am about to save copies of all of the layers in my mxd. I only want to save the top level group layers though. I have some group layers within group layers - I dont want to save them individually. ...
2
votes
1answer
267 views

How to enable the snapping options for vector layer using the python programming?

I want to enable the snapping options for the the existing layers using python programming. How can I do this?
2
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1answer
125 views

Converting Historical Railroad Systems Data from KML?

I'm writing a paper for an undergraduate economic history class and I'm interested in North American railways in the 1800's. I've found historical GIS data for the period here. The railroad data are ...
2
votes
1answer
203 views

How to iterate over features and abort iteration with keypress in PyQGIS?

I would like to run a loop with PyQGIS, it should wait for the user to press a key either SpaceBar or Escape to continue. canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.currentLayer() feat = ...
2
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1answer
266 views

QGIS toolbars source code

I can see the source code of the core QGIS plugins from the repository in github. But is there any repository of source codes for QGIS toolbars also?
2
votes
1answer
76 views

Python-OGR how update the geometry of a point

I need to change the coordinates (geometry) of some points in a shapefile. I can't find the good method. if ( zone[best_y, best_x] >= ( nb_pixel_area - toler) ) and ( zone[best_y, best_x] <= ( ...
2
votes
1answer
101 views

QGIS 2.6 : Programmatically setting key value pairs for ValueMap widget

Using QGIS 2.6 and Python 2.7 on Windows 7, I am trying to programmatically insert key value pairs into a ValueMap widget via a csv file. Issue is that some of the values are properly inserted and ...
2
votes
1answer
305 views

How to get shapefile extent from standalone script?

I am trying to obtain the extent of a polygon in a shapefile. I am running a standalone script which will create a grid based on the extent of the polygon. I have tried 2 methods: one from the ...
2
votes
1answer
92 views

Algorithm to determinate neighbor's position (N S E W) of parcels?

After my first publicaation Determinate Parcel Neighbors using PYTHON Where i was looking for a faster way to calculate parcel neighbors and position, and after succeeding that, but the result was not ...
2
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1answer
290 views

FieldMap in Arcpy Merge for Selected Fields Only

I am trying to use FieldMap in arcpy to merge only a few of the same fields from 8 feature classes. There are many different fields in all of the different feature classes, but I have identified the 9 ...
2
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1answer
297 views

Arcmap Maplex labeling engine bug workaround - labeling expressions won't recognize multiple spaces

I am labeling points in ArcMap using the Maplex labeling engine using a short Python script. The labels are rotated depending on an 'angle' field. def FindLabel ( [name], [city], [num] ): Buffer = ...
2
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2answers
134 views

Error 000358 or Error 999999 invalid SQL

i've been searching arround all the answers in the questions of Error 358 and beyond, but i doesn't fix my problems, i tried every post and so on the problems stills there. I make two options in my ...
2
votes
2answers
228 views

Output raster from IDW interpolation tool is from 3.40282e+038 to -3.40282e+038 in ArcPy

I am not familiar with Python in ArcGIS, so I used ModelBuilder first to set the environment and put the tool in. The model worked right and the output raster seemed good. Then I exported the model ...
2
votes
1answer
174 views

Find and replace text based on feature class attribute

I've been struggling with this problem for a few days. It seems to be more programmatic than geospatial in nature, so I'm open to suggestions to redirect this elsewhere. I have a text file ...
2
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2answers
203 views

Add both string and automated numbers in series to attribute table using field calculator

I would like to fill a column in my attribute table with an string that ends in a numeric value. Example: Object001 Object002 Object003 I would like to automate the process of filling in the ...
2
votes
1answer
388 views

Install QGIS on Ubuntu with GDAL built from source?

I am trying to install QGIS on Ubuntu 14.04. While I can easily install it via the package manager or apt-get, I find that QGIS, when installed, does not have Python support as expected. The symptoms ...
2
votes
2answers
455 views

Query for numeric field against text field that contains a numeric value

In my database, I have one field, Service_Day, formatted as numeric, which contains a single digit number 1 through 7 (for days of week). I want to compare it against another field, called Region, ...
2
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1answer
182 views

Using netCDF4 Python climate algorithm?

I have been working in Python with the Acaconda Python distribution to create code that accomplishes the following algorithm: I have multiple variable netCDF4 files [NCEP Reanalysis tmax(K), tmin(K), ...
2
votes
1answer
97 views

Trouble renaming layers using arcpy

Running ArcMap 10.1 So, I have a bunch of layers that all have the same name. I'm trying to rename them so that they have names that actually mean something. Everything runs fine until it is time ...
2
votes
1answer
3k views

Bulk insert with Python and cx_Oracle into st_geometry enabled table

I'm trying to make a bulk insert of a CSV file with Python and cx_Oracle into an st_geometry enabled table of an Oracle database with ArcSDE. I could do it with the method execute() of cx_Oracle but ...
2
votes
1answer
40 views

Is there a python version of qTuio? [closed]

Is there a python version of qTuio? qTuio is implemented in C++. However, I am currently trying to use pyqgis due to problems with C++ environment (I cannot even create a raster layer). Any help is ...
2
votes
1answer
171 views

How to print 2 maps in the same PDF page using PyQGIS?

I am trying to generate a one-page PDF document containing the following items: 1) On the left half, a full state map (say, New York State). 2) On the top right quadrant, a map that zooms in to one ...
2
votes
2answers
125 views

Using python to batch process lasclip - LAStools/QGIS

I am trying to use the python console to batch quite a few processes from lastools. I'm having trouble with the arguments to lasclip. clipped_las = processing.runalg('lidartools:lasclip', True, ...
2
votes
1answer
155 views

Determine spatial average of several tiff files

I am relatively new to GIS. I have a set of tiff files containing a raster each. I would like to average them, though their extents are slightly different. They each have their geospatial data ...
2
votes
1answer
713 views

How to create a Qgis python script to manipulate fields with some parameters?

I'm just beginning with QGIS. I have a shape file with 10 fields field1, ..., field10, and many thousands of data. I will like to automatize the next sequence (in a python script or a model): load ...
2
votes
1answer
58 views

Python Geospatial Development Error

I'm working through some examples in the Python Geospatial Development book by Erik Westra. On page 439, about setting up a tile map server, he gives the following code for calculating a bounding ...
2
votes
1answer
362 views

How to convert an esri world file .jgw into xy corner coordinates?

I'm trying to convert a .jgw (esri worldfile) into xy corner coordinates for a series of JPEG images im outputting using arcpy.mapping.ExportToJPEG(mxd, "E:\\TEMP\\" + str(x) + ".jpg", df, ...
2
votes
1answer
293 views

Shapely's simplify won't simplify any more

I have a multipolygon in shapely, and I want to simplify it until it has less than a certain number of points. When I use the preseve_topology=False argument to geom.simplify, I can get the number of ...
2
votes
1answer
271 views

PyQGIS reload a QGIS plguin

I have a plugin that has a psycopg2 connection to a PostGIS database. When i close GUI with the X-Button and open it again, all the widgets are filled with the data from before. It looks like the X is ...
2
votes
1answer
283 views

Nested conditional statement in ArcGIS on multiple rasters

I have a list of rasters in ArcGIS and I want to create a conditional (Con) nested statement based on all the rasters of the list. I want this to be reiterate through many lists (the number of rasters ...
2
votes
1answer
272 views

Subset multiband tiff file using Python in ArcGIS for Desktop?

I have a multiband (1140) raster file in tiff format that I want to subset. Each band represents a prediction of monthly rainfall (12 bands for each year) over a 95 year period (12*95=1140). I need to ...
2
votes
1answer
239 views

PostgreSQL PL/Python Function for “IF” condition

I am using OSM data to run pgr_dijkstra() for weighted-path calculation. But after importing OSM data using osm2pgsql I populated some additional columns into my ways table. So now it has gid serial, ...
2
votes
2answers
765 views

'QgsVectorDataProvider' object has no attribute 'select'

I want to create a tool layer in QGIS 2.4 that will select any vector features that intersect with that point. In my script I tried the following function: def selectFeature(self, point, button): ...
2
votes
1answer
124 views

Cut polygon shapefile with 2 parallel lines to derive new inside polygon?

Using Python scripting: How can I clip a polygon shapefile with parallel lines (polyline shapefile) to derive new inside polygon?
2
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1answer
227 views

Compiling custom plugins for QGIS on Windows

I've made my first plugin using plugin builder and I want to compile it. I read that I need two commands to do it under windows: pyuic4 and pyrcc4. But when I use any of these commands I get this: ...