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

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Is there a faster alternative to arcpy spatial join?

I am wondering if there is a more efficient method than using arcpy spatial join in python. I am currently using intersect and closest methods (including a near distance field) so would need ...
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1answer
54 views

why does arcpy function work in ArcMap python window but not from stand-alone script?

So I think I'm running into a data/schema lock issue, but I have no idea how to tell, or how to fix it for that matter. Here's the setup: I have this chain of gp functions: #extract elevations to ...
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2answers
130 views

How to create a series of points along multiple polylines at once in ArcMap 10

I have a series of polylines that represent linear vegetation (shelterbelts, etc). I need to convert these to a series of points equally spaced in order to add them to a different shapefile that ...
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1answer
30 views

Why does the python editor “Idle” reference two Python installations?

I have installed python 2.6 with ArcGIS 10.0 but also Python 2.7 for use with gdal. I have a problem at the moment with the editor "IDLE". When I right-click on a .py script, the idle editor ...
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2answers
63 views

PyQGIS: Speed up for adding features and attribute arrays?

Context: I'm writing a dynamic import tool for QGIS (2.2 to 2.5) with python. Datatype: Binary Datasets with environmental simulations from HPC which might contain millions of features and terabytes ...
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1answer
85 views

How can we merge the two selected features in a vector layer

I have taken one feature and find which are the neighbouring features to the feature which i have taken and then i have combine all those neighbouring features with my feature to make one feature. i ...
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51 views

How to add column to attribute table using field calculator with $length function?

I used the following code to add a separate column to the attribute table with the length of features. from PyQt4.QtCore import QVariant from qgis.core import QgsField, QgsExpression, QgsFeature ...
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1answer
119 views

How to load a WMS layer using PyQGIS?

Although there are some posts on this matter, there is no answer in anyone of them. This is why I am asking it again. One post I found was Raster layer invalid I read information from the following ...
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15 views

What's a python script to get count of attributes in feature class? [duplicate]

I would like to count the number of attributes in my feature class with python.
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1answer
44 views

How can I extract the data showed in Version Changes before reconcile/post process?

I want to make a script in python to extract the data about version changes before make the reconcile/post process. Is that possible? I trying to avoid use C# or VB script.
4
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2answers
107 views

Selecting points on one side of the road

I am a newby in python scripting in GIS. I have 2 shapefile: first one with roads and second one with points that contains address number and street name. I want to select these points from right ...
2
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2answers
55 views

Find coordinates of given raster value

I would like to get the coordinates of a raster cell with a given value. I suppose many cells can take the same value, in which case several coordinates should be returned. In my first problem I'm ...
2
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1answer
45 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
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1answer
72 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
44 views

GDAL Warp to clip a .tif: Works fine standalone, won't work in Python

I am trying to use the subprocess module to call gdal warp and clip a .tif using a shapefile. When I try the command in GDAL it works fine, but when I attempt to call it into a Python script it will ...
3
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1answer
53 views

How to get Listfields from Autocad DWG?

I trying to get LisfFields from AutoCad DWG, to arcpy Add-In, i have tried mxd = arcpy.mapping.MapDocument("CURRENT") Layers = arcpy.mapping.ListLayers(mxd) for Layers in Layers: ...
2
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3answers
76 views

Insert layer file to MXDs with multiple data frames using ArcPy?

I have 4 mxd's and I want to insert layer file to each mxd with position in the TOC. Each mxd has 3 and more data frame. I don't know why it does't work. I'm trying this code: import arcpy,os,sys ...
2
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0answers
29 views

Diminishing performance of gdal_polygonize in a python subprocess for GRASS to PostgreSQL

I have written a python script to polygonize GRASS rasters into a PostgreSQL database using the gdal utility gdal_polygonize: sub.call('gdal_polygonize.py -8 gdb/quercus/{0}/cellhd/{1} -f ...
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1answer
60 views

Using Field Calculator to fill out a list of unit numbers

I am adding address points for individual units in trailer/RV parks and I would like to be able to use the Field Calculator to assign the unit numbers. Is it possible to tell the Field Calculator a ...
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1answer
39 views

Installing libspatialindex on Windows 8

I need to use Rtrees to make some code I'm running faster. However, in order to use Rtree, I need to install libspatialindex. When I've installed packages in the past I've been able to either download ...
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1answer
52 views

PyQGIS setSubsetOfFields function in QGIS 2.4

I found the function setSubsetOfFields to filter fields in a layer in the PyGIS cookbook: ...
1
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1answer
35 views

GRASS scripting for producing multi-band raster

I am trying to loop the r.sun function within a Python script. Anyway, I seem not to understand how I can stack the raster maps each loop would produce into a single multi-band raster (preferably in ...
2
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1answer
87 views

Calculating area of polygon inside region?

I am new to geographic information systems and i need to calculate the area of a a polygon ( a circle to be precise) that falls inside the boundaries of a region, say a state or a country. For ...
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2answers
76 views

Non Matching Rows between 2 txt files [closed]

I need to compare 2 CSV files so that I can get the missing rows from each CSV. All column attributes in each row should match while comparison. So I have 2 txt files and I would like to compare one ...
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1answer
138 views

CSV Format change [closed]

Breakline Input File, Breakline Output file I get a breakline file from a CAD guy in below mentioned format. So I am calling this as a “Input” file. I am calling this as a “Output” file. I would ...
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1answer
65 views

Multiple Subsetting

Input File, XY min,max file I have a XYZ .csv file for a large portion of an area. I have another txt file which contains Box numbers, Xmin, Ymin, Xmax, Ymax. I would like to export a CSV file for ...
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3answers
87 views

Drawing some points in QGIS 2.4 using Python

I'm new to PyQGIS so here goes: Give a new QGIS project, how can we draw some Points on the map? I tried the following but nothing showed up. Should they be placed in a Vector layer before they can ...
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0answers
29 views

Convert DateTime field to Just Date in Label Expression

I have a DateTime field (ex: CreatedDate) and would like to only show the date with the label. How would I setup the label expression to do this using python?
2
votes
1answer
42 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 ...
0
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1answer
56 views

Programmatically Select a CRS in QGIS 2.4 using Python

When you run the following Python code in the Python Console of QGIS 2.4, uri = "file:///C:/data.csv?type=csv&xField=lng&yField=lat&spatialIndex=no&subsetIndex=no&watchFile=no" ...
3
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0answers
61 views

arcpy.mapping.ExportToTIFF fails to render layer?

Has anyone else had this problem? I have an mxd file with two layers in it, one of which is fairly 'heavy' (i.e. takes a minute or so to draw). All layers are visible by default. I have the ...
2
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0answers
70 views

Python script for dark object subtraction on Landsat 8 Imagery

Does anyone know of any python scripts that will allow me to conduct such a process? I am limited to open source software and have minor experience in Python.
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2answers
48 views

How to change field defined as REQUIRED to NON_REQUIRED in ArcGIS Geodatabase

I have created some feature classes in a geodatabase and also some fields using this sample code: arcpy.AddField_management("schools", "ref_ID", "LONG", 9, "", "", "refcode", "NULLABLE", "REQUIRED") ...
2
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3answers
81 views

Removing small polygons gaps in a Shapely polygon

I know this issue has been addressed before with different software, but I am looking for an approach with Shapely. I have a polygon with a very small gap on the interior of the shape: Here is a ...
1
vote
1answer
53 views

Running GRASS functions in QGIS 2.4 from python console

I am using qgis 2.4 and i am looking for the "easiest" way to execute e.g. the r.in.gdal function from the python console in qgis. Specifically for r.in.gdal, I could not found this function in ...
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2answers
43 views

How to take cosine squared of raster using python

I have an equation y = cos^2(x) where x is a raster. How can I write this equation in python?
2
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2answers
71 views

How can I select features based on another feature attributes?

Here is my case: I have a layer of features (buildings from a city) that is populated with polygons. This polygons have attributes : street name and postal code In the project I have another layer of ...
1
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1answer
46 views

QGIS Deployment in Citrix XenApp - How to Remove Pyramids from the image “properties”

I'm working on deploying QGIS 2.4 into a XenApp 6.5 desktop environment. We've tested QGIS to see if it will run in our environment on a test server and have found that building Pyramids with ...
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1answer
82 views

Use PyQGIS to import CSV and draw points using different color

A CSV file contains columns latitude, longitude and color. uri = "file:///C:/data/balls.csv?type=csv&xField=longitude&yField=latitude&spatialIndex=no&subsetIndex=no&watchFile=no" ...
2
votes
1answer
73 views

Add OpenLayers layer from QGIS's Python console?

On QGIS 2.4.0-Chugiak the Openlayers plugin is found under Web menu rather than the Plugins menu. How can you use the Python console to add a Openlayers Google Maps layer? The following code give us ...
3
votes
2answers
87 views

What is the best way to get from wkt to shapefile in Python?

I am querying tables from a SQL-Server database and would like to convert the table into a shapefile. It has wkt geometries and wkb as columns in the table, along with other attributes that need to ...
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0answers
131 views

py2exe ImportError: No module named _err

The .exe file generated with py2exe returns the following error: c:\Users\...\dist>ShapeFileConverter.exe Traceback (most recent call last): File "ShapeFileConverter.py", line 4, in ...
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2answers
38 views

Automating procedure to add shapefile to multiple map templates using ArcPy?

I have a project that has me create a package of about a dozen maps for a client and I do this multiple times per week. I am trying to figure out if there is a way to automate this with python. I am ...
1
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1answer
48 views

slow Python script pulling from an iSeries database

I've converted and updated some python scripts that exported data from an iSeries database (HTE) to Access to export the same data to a fgdb. My biggest issue is the time it's taking to export the ...
3
votes
1answer
78 views

Fast raster combine using rasterio

I'm trying to duplicate the functionality of ArcGIS's Combine function within rasterio. Given a list of (presumably categorical) rasters read with rasterio, I want to output a combined raster and a ...
1
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1answer
93 views

ExecuteError: Failed to execute. Parameters are not valid. ERROR 000732: Layer Name or Table View: Dataset L does not exist

Hi I am trying to create a loop so that each layer is produced in its own map. This is my code: import arcpy path = "C:\Users\Et\Documents\ArcGIS\Default.gdb" mxd=arcpy.mapping.MapDocument(path ...
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1answer
68 views

QGIS select reversed geometries

I have a road network and a geometry for each road direction. One Geometry from A->B and another Geometry from B->A. This geometries are covering each other. Is there a tool available in QGIS to ...
3
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0answers
87 views

Select and copy attributes features in ArcMap using Python add-in tool?

I'm trying to add a tool to an add-in toolbar to select features from an existing feature class and copy attributes to another feature class,from point to point. TopoHeight_Field_Name='Comment' def ...
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22 views

Script Efficiency

I have been working on a script to read pixel values and print the values out to a text file. This is currently working but takes around two hours with a 6.6gb file. This is to replace an older script ...
2
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1answer
37 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 ...