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

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53 views

How to successfully do “nested” looping over a Fiona collection

I wrote some code that basically loops over all features in a shapefile with Fiona in Python, doing some things, calculating some things, etc. I found that it would exit the for loop prematurely, ...
2
votes
1answer
78 views

python crashes with returned gdal band object from a function

I wrote these two functions in a module when I want to read the band in NetCDF or HDF files and return the band outside the function. Each HDF and NetCDF has many subdatasets. Each subdataset in a ...
2
votes
1answer
122 views

How to launch Processing tool User Interface using PyQGIS?

I am trying to launch the UI of a processing algorithm using Python script but I cannot find a simple way for it (aside double clicking on it in the process toolbox of course). The plugin is a water ...
2
votes
1answer
97 views

How to find if map layer registry is empty?

In my script I want to open layer named my_layer if it is in the map layer registry. I use following code for it: inputLayer = QgsMapLayerRegistry.instance().mapLayersByName("my_layer")[0] If not ...
2
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1answer
82 views

How to create a new empty memory layer with fields scheme from other layer in QGIS?

Being a complete noob with python so far, I got inspired by this answer: http://gis.stackexchange.com/a/155988/8202 to dive into it a bit. When creating features in a new target layer from an ...
2
votes
1answer
57 views

QGIS re-write loop efficiently, assign number to every row of a column,

I have a column titled CompanyNam and I need to extract the ownership information. For example, if CEZ is the first company then, I assign to it number 1, then Sokolovska is the next number, etc. If ...
2
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2answers
125 views

Reserved Ampersand Character in Label Expression of ArcGIS for Desktop?

I have this code which works... def FindLabel ([NUMBERNAME], [NUMBER], [BLOCK], [SURNUM]): lineone = "A:"+ [NUMBER] absName = "<CLR red='255'><FNT size = '14'>" + [NUMBERNAME] ...
2
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1answer
57 views

How to add a message bar to custom canvas?

There is a simple code to add message bar to main window in QGIS: iface.messageBar().pushMessage("Hello","World") My question is how to add bar to my custom canvas canvas = QgsMapCanvas() in ...
2
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2answers
182 views

QGIS/Python script to generate random points many times

Good day. Can anybody provide a simple code to be run in the Python Console of QGIS (I am using 1.8 Lisboa) to generate X number of random points (say e.g. 5000) over a certain global shape of ...
2
votes
1answer
75 views

Replace Expression in Field Calculator to include a Numeric Range

There has to be an easier way to clean up address data, I hope? GeoCoding, I need to remove APT# and any number or letter that follows.
2
votes
1answer
105 views

problems overwriting files in ArcSDE with python script

I'm having a great deal of difficulty overwriting files when using ArcSDE. The usual 'arcpy.env.overwriteOutput' method doesn't seem to work. When I run this script: import arcpy from arcpy import ...
2
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2answers
255 views

How to make a movie from a ascii grid files?

Lets say I have several ascii grid files for each time step for a particular location. I would like to spit out the image for each of these ascii grid files and legend on the side bar. I also would ...
2
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3answers
385 views

PyQGIS - load PostGIS layer as editable

I can load a PostGIS layer on QGIS' map canvas but "Toggle Editing" button comes "inactive". How can I load vector layer as editable? The code given below loads PostGIS layer on map canvas & ...
2
votes
2answers
255 views

How to use `layer.getFeatures()` in a standalone script?

I am following the QGIS Cookbook and this post where it concerns reading attributes from layers. I would like to exploit this method and implement it into a standalone script. Essentially, I want to ...
2
votes
1answer
922 views

Install gdal in python on Windows7

I'm having problems installing the gdal library for python. I use a Windows 7 and have WinPython 2.7.9.2 which runs Python 2.7.9. I'd like to use gdal + Python for raster manipulation. I've read ...
2
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2answers
215 views

What is the “best” way to automate the GIS slope and aspect algorithm?

I am currently obtaining slope and aspect of roofs using ArcGIS as follows: Mosaic several Lidar .asc files to new raster Extract by mask using Mastermap building outlines to get hold of just the ...
2
votes
1answer
198 views

Python tool won't stop running— Not an infinite loop issue

I'm having trouble with a python script. It is essentially a near duplicate of another script which is running fine-- it is using different files, but apart from that the tools used and the order in ...
2
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2answers
144 views

Script to convert line segments to equally spaced points based the duration between points as specified in another field

I have a single file containing several hundred line segments created through connecting points collected detailing animal movement patterns. Each segment has a "seconds" field and a "uniqueID" ...
2
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2answers
288 views

Batch add column to layers and add layer prefix in PyQGIS

I have a number of layers each with a prefix like A_ B_ and so forth. I'd like to: Add a column (text) called DENSITY to each shp Add the prefix letter from the layer name to each row in the ...
2
votes
1answer
571 views

Using ArcPy to Read from Excel Spreadsheet to Python Dictionary

How would I go about creating a script that reads a specified excel spreadsheet and places the values in a dictionary? I have read about the xlrd library and how the library in such endeavors to read ...
2
votes
3answers
67 views

QGIS python plugin appends values every time it's started

I've written a small python plugin (using plugin builder as base) to simplify the expression process for a given layer (just a few comboboxes that are used to create a query). The combo box populating ...
2
votes
1answer
312 views

Getting a number from QLineEdit and passing it to the buffer function

I am developing a plugin which finds buffer. In that i am using lineedit for getting distance from the user and pass it to the buffer function. My current code throws an error "'QLineEdit' object has ...
2
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1answer
357 views

How to move layers in the QGIS Table of Contents via PyQGIS?

I have loaded two layers in canvas and would like to move the layers using the following code in TOC, but it is not moving the layers to the position based on the index given. from PyQt4.QtCore ...
2
votes
1answer
340 views

How is the Python IDE aware of arcpy?

I'm using PyCharm 4 for some Python scripting. When I type import arcpy I can immediately start using items within the arcpy namespace, like the environment & workspace objects. How does the ...
2
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3answers
343 views

Why script works on my computer but not on another?

The script below works perfectly fine in my computer. But when running the script on another computer, I receive an error: Error: Algorithm not found The computer has similar specifications to ...
2
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2answers
535 views

Add multiple Layer files in subdirectories to mxd using python

I have more than 300 layer files located in many sub-Folders and sub-sub-Folders. All Sub Folders are located in one large directory.I read Use python to add layers to TOC and I try, with arcpy, to ...
2
votes
1answer
187 views

How to read X,Y from mouse click in Python

I am looking for some advice… I am trying to build a tool that will precisely (10digit, eg: AA1234512345) identify British National Grid (BNG) by clicking on a map. The ArcGis default tool can only ...
2
votes
2answers
282 views

Select Layer By Attribute to be used in for loop

I'm trying to iterate through a feature class and select each feature one by one by using the OBJECTID field. When I use a single value, the SelectLayerByAttribute works, but how do I compare the ...
2
votes
1answer
213 views

Command line error and missing dependency in QGIS

I have two problems with QGIS 2.6.1 1) When i am trying to open command line i get error: An error occurred during the execution of Python code: Traceback (most recent call last): File ...
2
votes
3answers
189 views

Using GDAL translate in Pythonwin

I want GDAL translate in Pythonwin to process some GeoPDFs to GeoTiffs. I can't call up GDAL module in Pywin. I used the OSGeo4 installer for original GDAL install and can leverage GDAL properly from ...
2
votes
1answer
121 views

geting geograpic locations from an address list

I have a table with 150 addresses. I would like to automaticly generate a point shapefile/PostGIS layer from all of them. Is that possible in any way or do I have to search for every single address to ...
2
votes
2answers
107 views

How to encode a point geometry in Geojson?

I have point geometry in posgresql which I query as follows: select ST_AsText(geom) as pointgeom from pointable. I'm using python as server side script. I want to pass the result as Geojson response ...
2
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3answers
2k views

Converting personal geodatabase .mdb file to .gdb

Is it possible to convert an MS Access personal geodatabase file to a SDE enterprise geodatabase file format? What kind of python scripting would it entail? I need to convert it in such way to ...
2
votes
1answer
63 views

Referencing fields in code block of Field Calculator in ArcGIS for Desktop?

I'm trying to use values from a field to fill a new field with a truncated version. The 'str.rindex' function is working out well, but I can't seem to figure out how I'm supposed to reference the ...
2
votes
2answers
407 views

I've downloaded the GDAL-1.11.1 package but why can't I call on it in python?

I have a Mac and am very new to this coding stuff.. I'm using a code that includes import osgeo as gdal and so I've downloaded GDAL from https://pypi.python.org/pypi/GDAL/ which has a folder ...
2
votes
1answer
121 views

Grass python shell can't find my data

I have a problem, the grass 7 python shell can't find my rasters. When I try to use the python shell to set the region I get "region not found". I can set the region in the grass shell (and other ...
2
votes
2answers
105 views

Returning value from other field, using FieldCalculator

I am very new to Python and need what I believe is a very basic script in order for my field to represent another fields' input, if the field's value is 0. I tried to search for this, but gave up ...
2
votes
1answer
100 views

Trying to generate a PDF for each feature in a feature class based on an attribute with Python.

I have a feature class of points that represent storm water inlets. I am trying to automate a process that does the following. finds all of the inlets that have a field called "Marker" populated ...
2
votes
4answers
341 views

Field Calculator Python Expression Issues

I'm pretty new to Python and this is my first post on this forum so I could use some help. I am currently attempting to run some code in the Field Calculator in a model in order to replace string ...
2
votes
1answer
405 views

ListRasters based on filename using Arcpy

I am trying to create a python script for ArcMap which calculates the ndvi from two raster images for each RGB/NIR pair in a folder. However, I am unsure how to create two raster lists; one which ...
2
votes
1answer
123 views

How to create Multipart Line in ArcPy?

I am developing some script in where I want to create custom multi part line geometry. For example: I have one array of points a,b,c and second array of points e,d,f. I want to create one ...
2
votes
1answer
347 views

Migrating data from Python to PostGIS

I have pandas DataFrame with these columns: point datetime value 1 Point(-24.6064453125 26.3683280945) 2014-09-11 19:00:00 24.885258 2 ...
2
votes
1answer
278 views

Python Use SearchCursor/InsertCursor to split attributes in fields

I download data daily and create a geodatabase table. Fields: Company, Customers_Active, Customers Total, County, State Example Data {CompanyA,CompanyB}, {141,424}, {1000,3421}, Cook County, ...
2
votes
1answer
663 views

Installing Pandas in ArcGIS 10.2 for Desktop?

I followed the very clear directions in the answer to Installing pandas with Esri's python? and created the Esri101 build and added a "conda.pth" file to my ...
2
votes
1answer
306 views

Unicode Decode Error for shapefile in Python

I have Python script for converting shapefiles to Geojson. My code works well if I use some usa data, but when I want to use some other encoding, it gives me this error: Traceback (most recent ...
2
votes
1answer
188 views

Open a .osm.pbf file with fiona in python

I would like to open a .osm.pbf using fiona in Python. I can't find much documentation on this. How can I does one do this? I have done it using ogr2ogr.
2
votes
1answer
87 views

Get min-max values of a raster and populate two parameters with the values in tool validation script

I am customizing the script tool behaviour of a custom script and would like to get the min-max values from a raster self.params[0] and populate the next two parameters, self.params[1] and ...
2
votes
2answers
74 views

Selection of lines that lays mostly in defined zone (majority overlap)

I have lines of surface runoff and I need to select the ones that are lying mostly in internal buffer of polygon. I'm trying to make some script in python, but it's very important to make the script ...
2
votes
1answer
195 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 ...
2
votes
1answer
144 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 ...