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

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1answer
53 views

Fastest way to process OSM

I've been working with imposm and Python, it's fairly easy to parallelise. I've hit a performance problem when trying to associate the coordinates to the ways. Creating a dictionary from ...
2
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3answers
186 views

ASCII file with latitude, longitude and data to GeoTiff using Python

I have a .asc file with three columns of data: longitude, latitude and a data value. Each latitude and longitude point represents the location of a centriod of a 1/8 degree unprojected grid. I want ...
2
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1answer
271 views

geopandas spatial join extremely slow

I am using the code below to find a country (and sometimes state) for millions of GPS points. The code currently takes about one second per point, which is incredibly slow. The shapefile is 6 MB. I ...
2
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2answers
42 views

How to select form the attribute table in with ogr

i want to select the (Sumava) from the attribute table and then make a shape file, my problem is i don't know which function should i use to select this area.if any one can help me? import ogr import ...
2
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2answers
186 views

Generate TIN from elevation data in Python (no Arc)

I would like to generate a 3d terrain model of an area, and I am stuck on creating the TIN (which I will convert to an STL). I know there are plenty of ways to use ArcGIS, QGIS, 3DEM, and various ...
2
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1answer
74 views

Create new shapefile based on values ranges in existing shapefile using gdal/ogr/python

I have a shapefile containing many thousands of polygons with values stored in an attribute field and ranging 0-105. I would like to create a much simplified file that contains classes for value ...
2
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2answers
228 views

Find country from GPS coordinates, offline using python

I'm aware that there are several similar questions already but I have been searching for days and not been able to solve my problem: All solutions I've found require GDAL, which I have not been able ...
2
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4answers
354 views

Python Library for converting GeoJSON Multi-polygon to polygon

I would like to know if there is a Python library that can be used to convert GeoJSON Multi-polygon to a Polygon. Note: i want to convert .geojson file Multi-Polygon feature type to Polygon feature ...
2
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3answers
159 views

Search and concatenate Landsat bands with Python

I have a number of Landsat geotiff (*.TIF) file in a folder. The problem is simple, I need to search certain Landsat bands from that list and make a composite tif image. I am using Orfeo Toolbox's ...
2
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3answers
277 views

How to create a Projection from a CRS string using pyproj?

I'm trying to convert between two coordinate systems using pyproj: import pyproj p1 = pyproj.Proj("+init=EPSG:4326") p2 = pyproj.Proj("""PROJCS["NAD27 / California zone ...
2
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2answers
182 views

Merging features (lines) in shapefile with same name using Python and QGIS?

I am working with the NHD flowline dataset (USGS) and some of the line features have the same name. I want to merge the line features that have the same name. For example: There are three features ...
2
votes
1answer
136 views

HDF5 and georeferencing?

I'm doing quite heavy processing of Earth Observation data, and it appears that a lot of my workflow can be speeded up by using HDF5 for local storage. I mostly work with large stacks of raster files, ...
2
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2answers
75 views

How to load stored composer from project file in standalone QGIS application?

I would like to load a .qgs file and get a composer from it, but I can't figure out how. Is there a way, or do I have to read the xml myself and individually set the appropriate values for the ...
2
votes
2answers
144 views

Store in a python list the attribute table of a vector in QGIS

I'm stuck with a very simple issue.. I've loaded in QGIS (through the py console) a csv layer (no geometry) made of 4 fields and 3 rows: #load the csv layer = QgsVectorLayer("path/to/the/csv", ...
2
votes
1answer
70 views

Dissolving a TIN using python/ogr binding

I have a TIN model where I remove some of the triangles (see fig. 1). Most of the triangles touch on one edge, some on one vertice. I would now like to generate a polygon shapefile containing the ...
2
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2answers
70 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
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1answer
102 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
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1answer
147 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
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1answer
179 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
108 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
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1answer
74 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
196 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
72 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
268 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
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1answer
83 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
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1answer
173 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
313 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
571 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
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2answers
350 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
1k 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
267 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
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1answer
243 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
185 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
362 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
798 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
88 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
667 views

How to add label to QgsVectorLayer by Python

my goal is to define label programmaticly for the case similar for the figure below: But didn't find any guidance how to do so using Python. I have a feeling it could be done using QgsLabel but ...
2
votes
1answer
411 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
votes
1answer
506 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
503 views

How to apply a filter to multiple vector layers in QGIS?

I am trying to apply an attribute filter to multiple layers in QGIS at once. The filter is to be applied to .osm data brought in through PostGIS to QGIS. I have tried selecting multiple layers -> ...
2
votes
1answer
429 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
412 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
votes
1answer
1k views

Where should PythonWin be located?

I have a question about PythonWin. Does it come with the DVD when you install it or does it have to be installed manually separately from the ESRI DVD ? On my computer at work, it does not come with ...
2
votes
1answer
211 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
406 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
241 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
243 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
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1answer
147 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
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2answers
120 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
3k 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 ...