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

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2answers
199 views

How to calculate monthly maximum values from daily data in a 365 band grd?

I have a MINT2005.grd file which has 365 bands representing days of year from 2005. Each band is a 32x35 matrix representing the temperature at different latitude and longitude pair. How do I ...
2
votes
3answers
529 views

convert a shapefile into graph with nodes and edges

Is there a way to convert a shapefile into graph with nodes and edges(except networkx). I'm using qgis and I want to convert a road vector layer into a graph, so that I can use it to apply shortest ...
2
votes
1answer
279 views

QGIS Python Scripting - Syntax definition

After playing around with the Model Builder and looking at the python scripts of what I make, I noticed some syntax which I can't find the definition anywhere. Here is a snippet of the python script ...
2
votes
2answers
639 views

How to create a Shapely LineString from two Points

If have two points, from which I want to create a straight LineString object: from shapely.geometry import Point, LineString A = Point(0,0) B = Point(1,1) The Shapely manual for LineString states: ...
2
votes
1answer
73 views

Finding Code in QGIS Select Features Toolset

Can anyone tell me in what directory the pre-installed Python scripts for the QGIS selection tools (i.e., Select by Point, Select by Polygon) are found? I am using on a Windows 7 installation of QGIS ...
2
votes
1answer
151 views

How to implement 1:n joins with string attribute concatenation?

I have a question concerning pyQGIS. I'm a QGIS long-time (self-learned) user, but just a pyQGIS newbie. I want to implement 1:n spatial join with attribute concatenation in the table. I have a vector ...
2
votes
1answer
465 views

Determine Equal-Area Slope of Longest Water Course in Catchment

I'm still very new to python and need some direction in developing a Arcpy\Python script to determine the Equal-Area Slope of the Longest Water Course within a catchment. The Longest Water Course is a ...
2
votes
1answer
225 views

How can I extract only band 4 from a geotiff multi bands to create geotiff or AAIgrid with this band using Python?

I have a geotiff file with many bands... I will like to create a .asc file or tiff file by converting only one band from the geotiff file. I don't find the solution by using python... With ...
2
votes
2answers
118 views

ArcGIS - Extract by Attibutes in Model Builder

I have a model which at one point uses the Extract by Attributes tool to produce a new raster with just the areas containing the maximum values of the first. I would think that the SQL expression ...
2
votes
2answers
196 views

Update raster value to reflect total number of points within cell- python

I have what should be a fairly simple task, but I can't seem to figure out how to do it. I have to do it in python/arcpy/gdal/whatever because I'm trying to automate this process for a hundred or so ...
2
votes
1answer
153 views

How to Format Description when writing Help for Python script tool?

I try to format the description in script tool but I don't know how it works so i don't manage to add a line break for example. Does it works with HTML tags ? When editing my script the description ...
2
votes
2answers
215 views

Why is arcpy.StackProfile_3d -> arcpy.SaveGraph_management creating empty graph?

In a python script I'm trying to save a graph to a .png file with graph output from arcpy.StackProfile_3d but the .png file shows an empty graph. The table created from arcpy.StackProfile_3d shows ...
2
votes
1answer
354 views

Using 'construct points' on all lines in a shapefile (arcpy)

I need to use the editing tool 'Construct Points' on several shapefiles that each have ~1300 polylines. I need to do this to create points every 1km along each of the polylines, which represent the ...
2
votes
2answers
240 views

How to save python ogr2ogr shapefile to memory, and stream to web client as zip

I'm trying to accomplish something similar to the site http://ogre.adc4gis.com/ I want to be able to manipulate a geojson file, and send it to the client as a shapefile, in a single zip file. I'm ...
2
votes
1answer
995 views

import qgis.core problem with QgsFeature and QgsGeometry

I've tried several previous answers to similar questions - no luck. I run Win7. I installed QGIS 2.2.0 using the OSGeo4W 32-bit installer. Problem 1) from qgis.core import * failed. Solution 1) ...
2
votes
2answers
254 views

How do I load mapinfo mid/mif into geopandas?

I suspect this is a trivial question to answer but how do I load mapinfo mid/mif files into geopandas? While it's trivial to load and manipulate .shp files, I can't work out what code to use: Here's ...
2
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2answers
799 views

What is the most efficient way to iterate through folders and geodatabases?

I am looking at cataloging some data, and I have code that works, it just seems to take a lot of time to run through all of the items. The way this data is structured is a bit of a hindrance, ...
2
votes
1answer
118 views

If Then Modelbuilder, Project error

I have a model where I want to check the projection. If it is GCS_WGS_1984, I want it to go one path, and if it isn't, I want it to go another path. I created a "Check Coordinates of Input" script ...
2
votes
1answer
301 views

Transferring data between spatial databases

I would like transfer spatial data from PostGIS to Oracle Spatial. I want to use Python's modules psycopg2 and cx_oracle. Transfer Oracle > PostGIS is OK, but in opposite version I have problem with a ...
2
votes
1answer
879 views

Read and Export OSM Road Data as a Network of Road Segments [Adjacency Matrices]

I wish to extract from an OSM file a road network, and export it as an array (adjacency matrix) where the nodes are the road intersections and the edges represent the road segments. I don't want to ...
2
votes
2answers
225 views

Can I use the LEFT (string) operator in ExecuteSQL()?

In QGIS I can use the LEFT operator on a dataset like this: LEFT( "Name2",3) ='031' What is the syntax for using this expression with ogr in python? Isn't this the right syntax? ...
2
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2answers
551 views

How to create equidistant points in QGIS along a polygon?

I am looking for a solution to distribute with a python script equidistant points in QGIS along a polygon. I tried to use the following code example: ...
2
votes
1answer
409 views

Automatic calculation in one attribute table based on values in another attribute table using python

I am trying to fill the fields of one gdb table based on some statistics over the attributes of another shape file. As it was not possible in ARCgis directly, I am trying to use python coe for this ...
2
votes
1answer
581 views

How to make autoIncrement number start with (001…009, 011…099)?

i have a challenge with my time in my work, i have feature class called "Parcel" storing many data, i generated an autoIncrement number by using field calculator, in field "parcel code" Expression: ...
2
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2answers
457 views

Why cant I use SelectLayerByAttribute_management while a cursor is set

I've been having a problem with arcpy in that the simple line: arcpy.SelectLayerByAttribute_management ("TEMP_LINES") produces this response: Runtime error : ERROR 000358: Invalid expression Failed ...
2
votes
1answer
105 views

Irrational feature ID behavior in a PyQgis script

I've written a script to determine the coordinates of a point shapefile and insert them into its attribute table. It works perfectly when the ID sequence of the indiviual features begins with 0, yet ...
2
votes
1answer
294 views

Which data providers support loading attribute tables without geometry?

I have a table in Memory from a cx_Oracle query (a list of rows, and a list of field names and their types) in my python plugin and I want to load it as a geometry-less layer (Attribute table) in ...
2
votes
3answers
120 views

How to analyze and combine overlaping elevation maps into one?

I have 30 overlapping maps that contain tree density heights (measures between 1-100%) of a large area, and I need to get the highest point by pixel and create a new map with all these highest points ...
2
votes
2answers
44 views

Assigning ID to features with similar attributes

I have a polygon feature with three attribute columns. The values in each of the attribute columns are number coded. I want to generate an ID (fourth column) for the unique combination of the values ...
2
votes
2answers
569 views

Find index location of a lat/lon point on a raster grid in ArcPy

This question has been confusing me for a while, and I'd love y'all's help. I'm trying to find the index location on a raster (in terms of column and row#) of a specified lat/lon point. My first ...
2
votes
1answer
343 views

How to assign values to field using if/then logic involving multiple fields?

I want to run a field calculation on a string field named [territory] that first looks at a string field [majr_src] to see if there is a value other than "NONE", if so [territory] = [majr_src]. If ...
2
votes
1answer
542 views

How to refresh Catalog window from ArcMap using Python?

I am running my script from ArcMap and I have the Catalog window open on the side. I delete some extra files in the end of my script but I have to refresh the Catalog window to see them go. So I ...
2
votes
1answer
842 views

How to use GROUP BY with arcpy.da.SearchCursor in file geodatabase?

fc = "C:\Users\AuxS3-4\Documents\ArcGIS/Default.gdb\Malla" fields = ('OBJECTID','Sentido','Carriles','idMalla') sqlclause=(None, "GROUP BY Sentido") cursor = arcpy.da.SearchCursor(fc, ...
2
votes
1answer
607 views

ArcGIS 10.0 get sde information out of .mxd

The overall goal here is to iterate through several directories of .mxd files and document which SQL Server instance of SDE they are pointing to, with the database name and feature class names. All ...
2
votes
2answers
92 views

Setting ProductCode for python script (Citrix environment)

I have set up a python script in ArcToolbox for our users. However when running it with ArcView 10.0 licensing the script fails with: ERROR 000824: The tool is not licensed I think it's an ...
2
votes
2answers
74 views

Accessing features via arcpy

i try to use arcpy to accessing the features of a shapefile. I tried to use a searcheCursor, like that: cursor = arcpy.da.SearchCursor(Points, ["SHAPE@XY"]) for row in cursor: x, y = row[0] ...
2
votes
2answers
619 views

Interpolation iteration using ArcGIS- arcpy

My current project requires interpolation of state level weather data. Approximately 5 years of daily data needs to be interpolated. I still need to figure out the best interpolation method. However, ...
2
votes
1answer
206 views

Model or Code to query all feature classes in geodatabase by selecting by attribute

I have a geodatabase that has 60+ feature classes that each contain records for 60+ locations. I need to export all records from each feature class for a specific location. In each FC there is a ...
2
votes
2answers
250 views

Group and export to pdf based on an attribute field using DDP - Python Script

Using Python, I want to export a map series. Each series needs to be grouped based on an attribute field which is not being used in DDP settings (page num, page index etc...). For example: my ...
2
votes
1answer
131 views

GDAL local files VS ftp files

I can successfully get raster information when the raster file is located on my local file system: import gdal from gdalconst import * filename= "MOD11A1.A2012193.h11v11.005.2012196013534.hdf" ...
2
votes
3answers
2k views

Python script for identifying duplicate records (follow up)

I am trying to calculate a field that marks duplicates and sequentially numbers them. I am using the code below that I found here: Generating sequential numbering for duplicate values in a field ...
2
votes
1answer
869 views

How to import sextante(processing) for QGIS 1.9 (2.0)

In the current QGIS development snapshot the SEXTANTE toolbox has been merged into QGIS and is now known as "processing". This is a good step, but the previous import command doesn't work anymore. ...
2
votes
1answer
66 views

arcgisscripting in CGI script

I'm trying to write a Python script that imports arcgisscripting (stuck on 9.3.1 here) which is then run as CGI by a web app. It runs fine from the Windows command line but as soon as I drop it into ...
2
votes
1answer
518 views

ArcGIS 10.1 Python script to snap points to lines

I have 2 Feature Datasets in a geodatabase. One dataset contains bus routes and the other contains bus stops for each route. I want to create a script that will snap the bus stops to the vertex of the ...
2
votes
2answers
766 views

Fiona ImportError: DLL load failed

I've been using the great Shapely/Fiona combo successfully on Linux, but now i need to create a kind of production environment on windows and theres only one problem. When i try to import fiona, i get ...
2
votes
1answer
178 views

Using Sum() or something similar with CalculateField_management and FieldLists

I need some help with using variables with CalculateField_management tool. I've tried several different scenarios but don't seem to have any luck. What I have is a list of fields containing water ...
2
votes
1answer
100 views

How to set default bad layers handler in the python plugin?

I am trying to write a python plugin for QGis. My python plugin will copy a template qgis project into data catalog with ESRI shapefiles. Because data catalogs can vary in its content there will be ...
2
votes
1answer
279 views

Using update cursor on a field with a domain

I have been replacing field calculations with python update cursors in many of my work flows and today I ran into a problem. The fields being updated have an attribute domain. so now, when I ...
2
votes
2answers
179 views

Why does QgsSpatialIndex::nearestNeighbor(point, 1) sometimes return 2 lines?

I'm trying to get the closest line to a point using pyQgis in a plugin. The active code file is this: http://pastebin.com/TDzmsKVM When I request the closest line (only 1) nearestIds = ...
2
votes
1answer
334 views

ImportError: No module named qgis.core

I am on Ubuntu 13.04. I get the following error message - Traceback (most recent call last): File "analyse.py", line 1, in <module> from log import shelve File ...