Tagged Questions

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

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1
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1answer
31 views

ArcGIS 10.2.1 working with time and reporting when feature geometry has changed

I'm working, with ArcGIS 10.2, ona whole lot of petroleum licencing data that chops and changes, in active areas, on a relatively frequent period. i collect the geometry data month by month (saving ...
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0answers
66 views

Exporting table of contents (TOC) with group layers to file geodatabase (GDB) with feature datasets?

I have created a python code for exporting shapefiles from TOC from different source folder to a output folder. However, in this case, I have some group layers in the Table of Contents (TOC). ...
1
vote
1answer
64 views

Listing all feature datasets and classes from multiple geodatabase into CSV file? [duplicate]

I have a folder having multiple geodatabase and I am calling that folder “Multiplegdb” There are 3 geodatabase in a folder which are as follows: ABC.gdb UVW.gdb XYZ.gdb Each geodatabase have ...
0
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1answer
56 views

QGIS Python - Convert the CRS of an in memory vector layer

In a python script of qgis I load layers from different datasources using the QgsVectorLayer() and the QgsRasterLayer() commands. The coordinate reference systems of the data sources differs. Since I ...
1
vote
1answer
45 views

Creating multiple Feature Datasets from table/list using ArcPy?

How to Create multiple Feature Datasets from a table/list. I can create a single feature dataset in a geodatabase with this python code. import arcpy from arcpy import env env.workspace = ...
1
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2answers
55 views

Creating a plugin tutorial

I am looking for a tutorial of how to create a plugin for QGIS. I want a tutorial that: Explains about the latest version of QGIS Working in windows environment. adequate for absolute beginners and ...
1
vote
1answer
150 views

Simple field calculator equation in ArcGIS 10.2.1 not working with python parser

I am trying to calculate a percentage in a field in a table. customers and total_customers are short integer fields. arcpy.AddField_management(tableSepSel2, "percent", "DOUBLE") ...
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0answers
67 views

Why will my field calculator python function always return Null if any inputs are Null?

I've written a simple python function that outputs a list based on yes/no fields. It appends a word to a list if it has a "yes" in another column then writes the list, formatted according to the ...
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0answers
91 views

Cumulative field calculation using Python in ArcGIS for Desktop?

I am using the following Python code to sum cumulatively but I need the summation to take place while the other field is equal to 1 and then again start the summation when it's equal to 2. I need the ...
3
votes
1answer
184 views

Extracting centerline of a Complex-Polygon in PostGIS/Python

Any idea how to extract the centerline of the following polygon (Fig1) using PostGIS functions or Python modules? I was trying Voronoi Function but thats not helpful for this kind of shape. I want ...
2
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0answers
87 views

N Nearest Neighbours efficiently PostGIS/Python

The data is worldwide about a million points, lat/lons, with an id and an importance value (0.0 to 1.0), and it's limited to being on land. Ideally I need to cluster all 1 million points into 100,000 ...
2
votes
1answer
63 views

Loading features attributes into numpy array

I am currently working on an add-on that relies on the user choosing fields of tables (that can be from shapefiles, csv or dbf) that are open in QGIS and then making computations with such data. ...
3
votes
1answer
123 views

Using if/elif for passing null values to Python of label expression in ArcGIS for Desktop?

I am trying to pass the Null values in label expression in advance python section. I have this code and it's not working. Note that all my values in [TX_SECT] and [ABSTRACT] are numbers. def ...
1
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0answers
47 views

Finding areas with high POINT density from PostGIS table using Python

I have a PostGIS table with thousands of POINT objects and I want to find areas that have a high density of points. I have the DBSCAN clustering algorithm implemented in Python which does exactly ...
0
votes
2answers
52 views

Parse PHP/HTML to shapefile or similar

I've been experimenting with scraping spatial data from a web page (www.majidata.co.ke). I've managed to find the source of the vector data from within a webpage though and have saved a chunk as HTML ...
1
vote
1answer
61 views

select random rows with python in arcgis

I am new to using Python in ArcGIS, and I wonder: how do I select random lines (or every two lines) of an attribute table? I must select these lines and calculate them, so they are different from ...
3
votes
2answers
146 views

Python code to compare two fields in different feature layers?

I have two shapefiles which encompass 3897 features each. Corresponding shapefiles (village and watershed that flows into it) have the same ID (ws_id in one, OBJECTID in the other). Many watersheds ...
0
votes
1answer
56 views

Cause of ExecuteError: ERROR 000539: Invalid field County Insets.OBJECTID Failed to execute (CalculateField)?

The following script joins two layers on a common id and attempts to use the OBJECTID in the joined table to update records for a field in the input table. In running it in "current" mode, it moves ...
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0answers
45 views

How to manage two map items in a QGIS composition with python?

I need to manage two different map items in the same map composition, with a stand alone python script. Each composer map has been referenced like this: composerMap1 = ...
2
votes
1answer
54 views

GDAL Python Not Working Correctly - Raster Calculations

I am sure this question has been asked and answered before. I am working with a x64 bit installation of OSGeo4W. I am trying to perform raster calculations using the gdal through the OSGeo4W shell, ...
2
votes
1answer
64 views

How to get into the Python API of QGIS?

After a few hours I am about to give up on finding a kind of documentation for the QGIS Python API that actually works/gives the correct information. It is obvious that there is no actual code ...
1
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1answer
38 views

QGIS raster calculator using abs() function

Is it possible to use the Abs() function in the raster calculator in QGIS? I've tried it, but it didn't work.
1
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0answers
43 views

QGIS processing framework SAGA NaturalNeighbor in external Python Script - No Output

I want to build a little script, which generates a NaturalNeighbor grid based on a point Shapefile. The script runs within my PyDev environment without any error messages, but no outputfile is ...
2
votes
1answer
69 views

arcpy with multiprocessing throws “UnpickleableError: Cannot pickle <type 'geoprocessing Layer object'> objects”

I'm attempting to speed up a process which is currently running synchronously, by using the python multiprocessing module. I'm having trouble sending a feature layer to a function which is called by ...
3
votes
1answer
60 views

Generate end points from a layer that contains multiple lines

I generate a layer file that has multiple parallel lines, that I want is to sequentially (from OBJECTID(1) to OBJECTID(Max)) create a point at each end point of the line segments and number these ...
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0answers
24 views

Setting up ArcPad applet (Python) that calls arcgisscripting?

I've been asked to support a legacy script that was "made" (read: found) by a former coworker. My python skills are pretty basic, so I went right to installing the applet like I would for a VBS ...
3
votes
2answers
117 views

How I can reverse numbers in a string without reversing any text? [closed]

I have a string, I need to reverse just the numbers in the string without the text: String: [321 test] The result will be: [123 test]
7
votes
1answer
291 views

Meaning of exclamation mark in Python parser of ArcGIS Field Calculator?

In the following line, I don't understand what those exclamation marks mean? And why put everything in quotation? I don't understand the purpose of the variable expression, please explain to me as I'm ...
1
vote
1answer
51 views

Populating Access (*.mdb) table with text from Text Elements to inventory MXDs using ArcPy/Python?

I am trying to write a piece of code to populate an Access mdb table with information from text elements in an mxd (text elements all have "names"). The purpose of this is to create a catalog of my ...
1
vote
2answers
189 views

Split a string column into 2 columns in python [closed]

I have a csv file and this is the structure of that file. It has only one column with number of strings. I want to split this one column into 2 columns at the character \. Can anyone please tell me ...
0
votes
1answer
43 views

Explicitly close a OGR result object from a call to ExecuteSQL

How can I explicitly close/release the result of an ExecuteSQL statement when querying a Spatialite database with OGR via Python? I have a simple query to return the SRID of a dataset. This works as ...
1
vote
1answer
97 views

List all Feature datasets & feature classes from a single geodatabase into CSV

I have prepared a python code and I got the following errors: "Parsing error IndentationError: expected an indented block (line 11)" and "Runtime error Traceback (most recent call last): ...
0
votes
1answer
36 views

Handling KML/CSV with geopandas - DriverError: unsupported driver: u'CSV'

I'm trying to import a dataset of UK postcode districts UK postcode districts from Google Fusion tables into geopandas with the aim of splicing it to a dataset of house prices. The problem is that ...
2
votes
1answer
72 views

Python to change file names in a directory

I am converting a directory of kml files to 1 single fGDB, but they all have the date as the file name. This creates a problem when using the original name because of the number at the beginning of ...
-1
votes
2answers
92 views

arcpy.Delete_management(“”) not working

I've written a script in a python toolbox. That script creates a folder in the user defined workspace for all the output files that are created during the script process. When the script is done, I ...
0
votes
1answer
57 views

Label related records in ArcMap from enterprise geodatabase

Two questions related to labeling 1:M related records in ArcGIS 10.2. I have successfully built an Advanced Label expression in Python to label records from a related table. I am currently working ...
0
votes
1answer
23 views

How can i automatically display the output of my toolbox?

i have made a python toolbox (.pyt file) and run it in Arcgis 10.1. The Output is a raster and I want it to automatically show up in the Arcmap viewer. The option for displaying the output of ...
1
vote
1answer
24 views

Find Polygon in “Layer A” containing Polygon in “Layer B”

I haven't found yet someone with the same problem, so I'm posting a new question. The topic seems quite standard, so I'm sure there's a way to do it in QGis. I have 2 layers: Region Layer Postcode ...
2
votes
2answers
46 views

Problem with accessing the layer legend using pyqgis in QGIS 2.4

I'm trying to clear the layer selection using pyqgis. It appears to me that: lgd = iface.mainWindow().findChild(QtGui.QTreeWidget, "theMapLegend") Doesn't work in QGIS 2.4 to access the layer ...
2
votes
2answers
38 views

Assigning a vector to a field in feature class (UpdateCursor)

I don't know if my mistake is of a general nature. I come from R where it is very easy to store a vector in a matrix column. So now I (new to coding with arcpy) am desperately trying to do the same ...
2
votes
1answer
107 views

Clipping Line shapefiles within extent of Polygon shape?

My question is an extension of Vertical lines in a polygon shapefile. Kindly refer to that question first. What you shall see there is a method of generating vertical lines with respect to the ...
1
vote
0answers
21 views

Ungenerate command in ArcGIS for Desktop? [duplicate]

I am searching for the ungenerate command in argis10 desktop. I get to know that is available only for workstation. But i don't have workstation. Is there any way to use this command or any other way ...
2
votes
1answer
76 views

ringer: help convert simple plugin to new QGIS 2.x

I have been trying to get this simple plug-in to work on QGIS 2.x. So far i got it to load, but it does nothing! all that it is supposed to do is place a polygon where a hole (ring) is. The code is ...
1
vote
1answer
94 views

How to calculate unique IDs starting from highest current ID

I have been using a python script in field calculator in ArcGIS 10.2 to add unique IDs automatically, however there are two things I would like to improve this process: Each ID also has letters at ...
3
votes
0answers
27 views

Overriding the QGIS Feature Dialog

We are developing a QGIS plugin and would like to override the QGIS Feature Edit Form with our own Dialog. Have explored using setEditForm and setEditFormInit, but the init process appears to want to ...
0
votes
0answers
37 views

ArcPy PointToRaster memory locking error solution?

RasterToPolygon ArcPy tool fails on generated raster (PointToRaster) with large(?) dataset. Not sure the size threshold, but fails on 78559 x 33544 raster, completes on smaller datasets so I know ...
0
votes
0answers
171 views

Transforming between epsg:3857 and Google Maps Tile coordinates

Hio, I used to use a simple python project (https://github.com/hrldcpr/mercator.py) to convert between wgs84 and google maps tile coordinates. This project doesn't have a license, and looks like it ...
1
vote
1answer
65 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
62 views

How do I link OGR with spatialite?

Problem & Evidence: I'm trying to create a spatialite file with the code snippet below. However the outDataSource object gets assigned NoneType and all subsequent (unshown) code fails. I'm ...
2
votes
1answer
65 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, ...