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

learn more… | top users | synonyms

1
vote
1answer
133 views

GDAL Merge Py on ubuntu many tif tiles into one

Trying to batch mosaic 1000 Gtiff rasters (all in one folder) into 1 tif file via gdal merge on linux ubuntu. Having trouble with the linux command to bring in all files in a folder into the output ...
1
vote
2answers
98 views

Vertical lines in a polygon shapefile

I am working with a GIS problem using a single input of a polygon shapefile. Consider an irregular polygon. I want to draw vertical lines across the extent of the polygon at equal spacing. How I ...
1
vote
2answers
302 views

Error "unsupported operand type(s) for +: 'int' and 'NoneType' for variance in python

I recently came up with an error in a script I am working with in Python for ArcGIS 10.1. The strange thing about it is that this script works for some files and not for others. Any ideas as to why ...
1
vote
1answer
36 views

Standard SQL with ArcGIS

Is it possible to use Python to run actual standard SQL on an enterprise geo-database? Think about batch deleting, joints, etc moving beyond just the cursor objects in Arcpy. Note that one can ...
1
vote
2answers
49 views

How to skip over errors created by cursors running through empty tables?

I am trying to automate the creation of many different feature layers were their content is created by a cursor. Sometimes during the automation, a feature layer may be empty, this is okay, but as the ...
1
vote
3answers
87 views

How to generate automatically the name of output parameters in a python script tool? [closed]

I have some Python script tools in ArcGIS for Desktop. I need to reproduce what all geoprocessing tools do when the first input parameter is introduced: autogenerate a workspace and basename for the ...
1
vote
1answer
65 views

trouble with code block execution in python script

I am trying to calculate values for a field in a python script, but keep getting an error that I don't understand: ExecuteError: ERROR 000539: Error running expression: Fron000000F1 Traceback (most ...
1
vote
1answer
274 views

Installing pandas with Esri's python?

Trying to get pandas to import, but I'm getting what looks like an error caused by a failed dependency of the version of my Esri-provided numpy's compile, based on this stackoverflow posting. Here's ...
1
vote
1answer
84 views

How to delete column/field in PyQGIS?

How to remove or delete column fields in a shape file using python?
1
vote
1answer
51 views

Con() does not recognize raster values

I have a problem when using the con() argument. What I want to do is to remap all raster of a raster file ("Red_SL") cells with values larger than 40 to the new value 5. All other values should be ...
1
vote
2answers
100 views

How to find the minimum pixel value within a region of interest?

I am working on a Python script for dark object subtraction, a radiometric correction method for remotely sensed data.To accomplish this, I need to find the minimum band pixel value of a waterbody ...
1
vote
2answers
334 views

QGIS 2.4: plugin changes map tool canvas click behavior from 2.0

I had created a plugin for QGIS 2.0 to add new features more easily. It involves changing extents and updating snapping options along with triggering the default actionAddFeature(). However, I've ...
1
vote
2answers
76 views

Python query to find records with more than one alpha character in a field

Using ArcGIS Desktop 10.2. I have a field in a table of several thousand records. The field is made up of alphanumeric characters. I'd like to perform two queries using python on this field: ...
1
vote
3answers
201 views

How to Build a graph from a map

I spent days looking in all questions here and trying tutorials. I need to build a graph for a region (It will be my input in simulation) I downloaded Postgresql and Postgis and osm2pgsql. Now i can ...
1
vote
1answer
66 views

Can't get SRS from PostGIS using Proj4 text

I'm having a problem transforming a point from the Australian MGA UTM datum (eg MGA Zone 51 http://spatialreference.org/ref/epsg/28351/) to WGS84 using GeoDjango. I've narrowed that down to a problem ...
1
vote
1answer
81 views

Arcpy: List to point feature class

I have a list of lists that contains: [vala, valb, valc, vald, (pntx, pnty)] [vala, valb, valc, vald, (pntx, pnty)] [vala, valb, valc, vald, (pntx, pnty)] I also have a list of the field names that ...
1
vote
2answers
246 views

Calculating distances between points two feature datasets

I will do my best to explain my problem. I have two feature datasets. One set has about 100 points that are "city centers." The other dataset has points for each census tract in each of these 100 ...
1
vote
1answer
92 views

Fix Black Border in Python Batch Raster Conversion

I have a Raster image like this as you can see the road are not connected between 2 raster (up and down) its because the scanned raster use different projection (dgn utm 50s) than my data frame (utm ...
1
vote
2answers
553 views

Create Feature Class From XY Table Using Python

I have some txt files that are basically attribute tables (object ID, latitude, longitude, area). In ArcMaps, I have been converting these files into feature classes and saving them in a geodatabase ...
1
vote
2answers
101 views

Running a Focal Mean or Low Pass Filter or 3 by 3 Mean Kernel in GDAL \ gdal_calc

Hi I am looking to run the equivalent of Focal Statistics in gdal_calc. Is it possible? It is a simple focal I require. I need to run a 3 by 3 kernel over the data (mean) and if possible only on ...
1
vote
1answer
88 views

how to assign keyboard key to python script in arcmap

I have a python script and I use it through my toolbox but I use it many times in a day. Is it possible to assign a keyboard shortcut to my tool ?
1
vote
1answer
220 views

Creating grid polygons from coordinates using R or Python

I have locational data with north-south and east-west coordinates, with a resolution of 100 meters squares. Each data point's location is somewhere within the 100 meters square which centre is given ...
1
vote
1answer
70 views

How to open most recent directory using PyQGIS?

For example, when I add a vector layer, next time that I want to add another layer it opens up where I chose my last layer from. How would one implement this in Python and/or PyQgis? I'm writing a ...
1
vote
1answer
110 views

Error with data frame in python script

I'm running a python script from arccatalog and it works, however, I am trying to add layers to an mxd and need to declare the data frame. I keep getting this error message. type ...
1
vote
1answer
187 views

How to get Z attribute of point using Python and ArcGIS Desktop 9.3?

I am making a python code for arcgis 9.3. In this code i create a new point with x,y and z attributes as following : rowsLine = gp.updatecursor(line_Feature_Class) rowLine = rowsLine.next() ...
1
vote
1answer
61 views

Why does Animal Movement toolbox give SyntaxError: invalid syntax?

I found a complete toolbox (Animal Movement tbx, by Regan Sarwas) for my tasks and I tried it. I had a systematic problem with the codes for all tools (line 1), for exemple: Executing: ...
1
vote
1answer
175 views

How to call ogr2ogr from command line with Python 2.7 from ArcGIS 10.2 for Desktop?

I am trying to access ogr2ogr in the command line, and this is the message I receive: 'ogr2ogr' is not recognized as an internal or external command, operable program or batch file. This is ...
1
vote
2answers
293 views

Counting Characters using Field Calculator - Arcmap

I am trying to use field calculator to populate a column based on the the number of characters in another column. I am using the Python Parser. I am not sure if the .count() function is appropriate in ...
1
vote
1answer
73 views

Python in ArcGIS, CalculateField_management, updating with single value

I have a float field which I want to simply update all values with 1. I can easily do this within the field calculator but I have started using python today, what is the syntax to simply update a ...
1
vote
1answer
120 views

Python.dll could not be loaded with PyScripter

I'm trying to configure PyScripter with QGIS. I've installed it using OSGeo4W and I'm following instructions to setup a pyscripter.bat file by copying content of qgis.bat file. I have the following ...
1
vote
1answer
159 views

Python syntax error -can't figure out why? [closed]

This should be simple. I hope I don't get down votes! I just got the following code from an article about using Google Maps API and ArcGIS to calculate routes without network analysis and just can't ...
1
vote
1answer
234 views

PostGIS Type Modifier Error

I'm trying to work an example from the "PostGIS Cookbook" and I'm getting an error I don't understand. I'm running the example using Postgres.app on a MacBook. Postgres.app is running PostgreSQL ...
1
vote
1answer
602 views

Import shp to Postgis using Python and ogr

I just export a Postgis Table to shp using this tips but I'm not able to import a shp to Postgis using the same library(ogr). Any idea? Thanks a lot f.
1
vote
2answers
55 views

Is there a tool that allows the same functionality of extend/trim feature that was available in 9.3?

In ArcGIS 9.3 there was a tool called Extend/Trim Features that allowed you to select multiple segments and extend or trim them to a feature. In 10.1 that seems to have been moved to the Production ...
1
vote
2answers
1k views

os.system /subprocess.call error handling when error in command line function?

In my Python script I call a GDAL utility using: subprocess.call('gdal_rasterize -a ICE_TYPE -where \"ICE_TYPE=\'Open Water\'\" -b 1 -burn 5 -l ' + shapefileshortname +' ' + shapefile + ' ' + ...
1
vote
1answer
66 views

Arcpy MosaicToNewRaster problem

I can't seem to get the mosaic created for this. import arcpy arcpy.env.workspace = r"C:\projectTemp\FloodAnalysis\output\2yr\raster" arcpy.env.overwriteOutput = True srName = ...
1
vote
1answer
258 views

What is correct Where Clause when using variable and Select By Attribute tool within loop?

I have seen several similar posts related to this technique but I am still having issues. The following script is intended to select all points from one shapefile that are within the boundaries of a ...
1
vote
3answers
215 views

How to prevent ArcGIS SOC from locking Oracle tables?

I have a python geoprocessing that performs CRUD operations on feature classes and oracle tables. Sometimes, when handling Oracle tables, ArcGIS SOC gets hung and locks the Oracle table. I need then ...
1
vote
1answer
185 views

Flow Direction Arrows in python

Any help would be appreciated. I am trying to write a python script to determine flow direction on a water pipe network. I have calculated the mid point of each section of pipe and created a point ...
1
vote
1answer
100 views

Unsupported operand error writing to file (Python, arcgis)

In the code below, I get a "TypeError: unsupported operand type(s) for +: 'NoneType and 'str'" on the f.write line. If I don't concatenate, it runs fine, but all the layer names run together. I ...
1
vote
1answer
188 views

How to reset ObjectID after running Delete_Features on SDE feature table?

I have a python script that deletes all features on a SDE feature table and then inserts new features to it. I noted that the ObjectID keeps incrementing from where the last feature was with before ...
1
vote
2answers
343 views

Off by about 85 meters when converting NAD27 UTM to WGS84 lat/lon

Looking through other answers on converting to or from NAD27 CONUS, I don't see an answer that seems to fit my problem. I am creating paper topographic maps by layering information derived from USGS ...
1
vote
1answer
169 views

Automatically determine polygon overlap 'islands'

I have a shapefile with many polygons. Some partly overlap with each other, some are not overlapping. I'm considering a polygon to be overlapping given a minimum area of overlap. 'Islands' of partly ...
1
vote
1answer
189 views

Python code intended to merge files in subdirectories… not producing merged result

The short python code below is intended to merge a series of files (GIS files) which are contained in a series of subfolders. import arcpy import sys import os PointsMerged = ...
1
vote
2answers
96 views

how to identify qgsvectorlayer area?

I need to identify the area from Qgis qgsvectorlayer anyone have an idea how to do that in python ?
1
vote
1answer
167 views

Python/GDAL: Best way to read in raster for use in A* search algortihm

I want to create a least cost path program with Python and GDAL since I couldn't find any open source cost path additions for use in Python. As recommended here the best approach is to use A* ...
1
vote
1answer
141 views

GDAL reports no bands for a 12-band raster and no projection either

When opened in ArcGIS, the raster correctly unfolds 12 bands, but when I try to open it with GDAL through Python, it appears as a raster that has zero bands. Here is the code: import gdal from ...
1
vote
2answers
316 views

How to add a dynamic timeline to the QGIS canvas?

I am using the plugin Timemanager which works really great but there is one thing I'd like to improve. Instead of displaying the date and time on each frame, I would like to display a timeline ...
1
vote
1answer
159 views

pulling an excel sheet with =rand(between) in a Python while loop, and exporting results as .dbf

To preface my question: I am very new to stack overflow, and relatively new to Python. I am working on setting up a sensitivity analysis. I am working with 40 parameters that range from 0.1 - 1. My ...
1
vote
1answer
265 views

Connect not working for custom QGIS form

So I have a custom form for editting feature attributes. However, I can't seem to correctly disconnect and reconnect certain bindings. The init code is below and should work for any simple QT widget ...