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

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251 views

How to automate performing analysis (intersection) between objects within different feature classes, for large number of objects?

I have two tables of roads - the same roads, from different sources, and am trying to compare how similar their positions are. I'm wanting to buffer each road in one of the feature classes and ...
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0answers
9 views

AddFeatures returned values …?

i try to add Features in a polygon vector layer. i'm using for example the following lines : fet.setGeometry(ft_com.geometry()) bool=pro.addFeatures([fet]) bool returns me True (i see the added ...
0
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1answer
34 views

How to use a wildcard for a field to sort many shp

I want to use a wildcard for a field so as to sort a group of shapefiles. All of them have the same columns but there is one column in each of them with only the first 4 characters common. Is ...
2
votes
2answers
127 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 ...
1
vote
1answer
358 views

Using GDAL to read dted files

How do I get the elevation at a certain point using gdal to read in a dted file? I don't see much useful information out on the web. I'm sorry I should have been more specific. How would I ...
2
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0answers
27 views

How to clip or erase a csv file with a non-rectangular shapefile?

I can clip a csv file with a ogr2ogr having 4 extents of a rectangular polygon. Is it possible to clip a csv file with a non rectangular shapefile?
0
votes
1answer
195 views

Grass 7 on Ubuntu 14.04. Can't start Grass

I attempted to install GRASS GIS 7 on ubuntu 14.04 using these instructions. When I call grass70 from the command line I get a welcome message and a prompt to continue. I then get two error messages: ...
2
votes
1answer
197 views

Is it possible to run a search cursor on a multipart feature class?

I have a multipart feature class of cities. I want to run a search cursor on a cities feature class where: one city is selected and a select layer by location is run to select all parcels that are ...
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0answers
194 views

How to read out the geoPDF data downloaded from USGS ned database?

How do I read the GeoPDF data that I download from the National elevation database from USGS? All I am looking for is lat/long/height for each point as much as the resolution would allow for a ...
2
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3answers
103 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 ...
4
votes
1answer
169 views

Merge tif files with python

I'm also having problems with running gdal_merge.py within another python script and I cannot run it. I already checked a similar problem here. My example is as follows: First I set my workspace and ...
1
vote
1answer
48 views

How do you use Windows folders as acrpy Parameters

I am having problems trying to perform simple folder management operations in an ArcGIS python toolbox. First here's some code snippets (I have left out all of the stuff that does not pertain to this ...
3
votes
1answer
197 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 ...
0
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0answers
36 views

google geocoding api usage restrictions and other free api options

I would like to use the google geocoding api to geocode a few thousand addresses. I understand the daily limit for a free account is 2,500. I want to retrieve the coordinates and then map them in ...
0
votes
0answers
26 views

Importing tif image from PostgreSQL Database to webpage

I am trying to import tif images from PostgreSQL Database to my website. In the website, I need to make a button control which will open the images. I think I have to use Pyhton as a server side ...
0
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0answers
42 views

How to create a Shapefile of a subset of input features in PyQGIS?

I'm having some trouble applying my Python skills to develop some scripts in PyQGIS. For me it's far simpler to write it in ArcPy, but then again I wouldn't get that much satisfaction after finishing ...
2
votes
2answers
182 views

UpdateCursor on two tables with value from SearchCursor

I try to keep myself busy and learn some python. I have two tables test2.shp (for searchcursor) test.shp (needs to be updated) I want to update test.shp with a UpdateCursor. The column which ...
0
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1answer
37 views

Can't get the correct version of GDAL installed to use ReadAsArray without getting error in Python

Using the instructions here . . . https://pythongisandstuff.wordpress.com/2011/07/07/installing-gdal-and-ogr-for-python-on-windows/ I downloaded the following files: GDAL-1.11.1.win-amd64-py2.7.msi ...
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0answers
27 views

Identifying Left and Right Mouse Button Clicks in PyQgis application

I am relatively new to PyQt. I am trying create a custom plugin for Qgis which enables the user to select some features by drawing polygon on the canvas using mouse clicks and then performs ...
0
votes
1answer
19 views

Batch Mosaic Rasters: arcpy.MosaicToNewRaster_management (ERROR 000628: Cannot set input into parameter coordinate_system_for_the_raster)

I am trying to batch mosaic rasters using arcpy.MosaicToNewRaster_management in arcpy: #This is for mosaicking a lot of rasters import arcpy from arcpy import env ...
0
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0answers
22 views

Quick way to select by attribute and zoom to selection in QGIS

I need to visually control hundreds of points in a layer on top of aerial photographs. Using the attribute table, selecting (with column filter expression) and zooming manually is cumbersome - so I ...
1
vote
1answer
168 views

How to do supervised image classification in saga with the help of R script or Python script

I am using Ubuntu 12.04 and want to do image classification in SAGA. SAGA has numerous classification algorithms which is not present in GRASS and QGIS. I am new to SAGA, but more accustomed to work ...
3
votes
1answer
703 views

How to access all mxd files in a folder?

I'm a beginner to Python and am trying to figure out how I can access several mxds in a folder. For example, when I want to use the AnalyzeforMSD function in ArcGIS: import arcpy mxd = ...
0
votes
1answer
67 views

OSGeo4W and GDAL - gdal2tiles.py error

Wondering why gdal2tiles is throwing errors, I've added the gdaldata and gdalplugins environmental variables and my python is at Python27/ArcGIS10.3/, and am wondering if that is messing with the ...
3
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0answers
53 views

Field Calculator convert text to integer then populate new field with sum [closed]

I have a .dbf with about 50 text fields containing numerals, I would like to convert those to integers and then sum them all in a new double field I created, is there an easy field calculation that ...
3
votes
1answer
63 views

ArcMap 10.3 - Anything Python related causes crash to desktop

Problem: ArcMap crashes to desktop anytime I use a Python related function (Toolboxes, Field Calulator, Etc) How I got to this point: I was trying to gain some familiarity with Python programming ...
1
vote
1answer
30 views

Auto-update a feature class with Python + .csv?

I am hoping to find out how to automatically update a feature class. We have semi-regular updates to an ArcGIS Viewer for Flex website. Looks like a Python script may be the way to go about it (and I ...
2
votes
2answers
204 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 ...
5
votes
2answers
129 views

Advanced python labeling in ArcMap - working with null values

I'm trying to label certain features using a specific field (osm_name_58_en). However, when this field is null, I want to label the feature with (som_english_32_name). If both are null then I want ...
3
votes
4answers
177 views

Removing first and third zeros of a fieldname in label expression

The fieldname only has three characters. I dont want to display zeros in the first and third values. example below. 010 = 1 100 = 10 01Y = 1Y 10Y = 10Y I have figured out how to strip out zeros ...
6
votes
2answers
507 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
1
vote
1answer
29 views

QGIS Python Scripting permission denied

I've just started a Python Scripting tutorial on QGIS. The problem arrives right at the end, when I have to use this script: output_file = open('c:/Users/Ujaval/Desktop/airports.txt', 'w') for f in ...
3
votes
1answer
190 views

Dynamic title in ArcMap

How can I have a dynamic title of the map, which changes depending on the layer chosen? Is this doable? It would save a lot of time and iterations since I should be producing several maps. To ...
1
vote
1answer
663 views

Linux Client for OpenGTS server

I've installed an OpenGTS server and successfully linked it with the GPS2OpenGTS_Pro application for android. The buses I'm tracking offer 3G with a wireless AP, however whenever the bus stops, the ...
3
votes
1answer
675 views

Getting unicode encode error in ArcPy/Python script?

When I am running a script (it checks to which database a mxd is connected) I get the following error: return codecs.charmap_encode(input,errors,encoding_table) UnicodeEncodeError: 'charmap' codec ...
2
votes
2answers
66 views

Cutting a polygon out of another polygon with python [duplicate]

Licence: ArcEditor Version: ArcMap 10.0 i have some issues to separat my data with python. To illustrate the problem, i have simplifyed the data with figures. I want to cut the blue polygon ...
1
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0answers
29 views

GDAL equivalent to ArcGIS Union?

I have a single shapefile full of overlapping polygons. The ArcGIS Union tool will generate individual, non-overlapping polygons with that geometry. Is there a way to do this with GDAL/OGR or another ...
1
vote
1answer
72 views

QGIS processing script: Move points by specified distance and add segment

I try to move points (they come as WGS84, but I'm not sure if it works with unprojected CRS) by a specified distance and connect original and new point with a line segment with the below script, but ...
1
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0answers
14 views

Cloud and cloud shadow identification with MERIS

I am looking at MERIS images to use for marine applications (Chl-a. SPM) and would like to confidently remove cloud and cloud shadow pixels from the data. I have a few ideas: Using the blue band ...
0
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0answers
13 views

Create a list of affected tiles from polygon / Gridding a polygon

Given a projection, a zoom level, a grid definition and a coverage polygon - what is the easiest/fastest way to obtain a list of map tile indexes touched by the polygon? Are there any existing tools, ...
1
vote
1answer
128 views

Esri Python Toolbox(pyt) corruption in ArcToolbox.dat

Symptoms: Open ArcCatalog and all tools within Python Toolbox(pyt) have a red-x error next to them claiming that "Arcpy module has no attribute Parameter" Close ArcCatalog Delete ArcToolbox.dat file ...
3
votes
2answers
110 views

Python labeling expression using numeric field not working

I'm trying to label parcels from a shapefile in the Python expression below in ArcGIS 10.2. All parcels should be labeled with the last 8 characters of their [PARCEL_NUM], and parcels 10 acres or ...
0
votes
1answer
49 views

Problem with scripts and tools in ArcGIS 10.X [closed]

I'm trying to figure out what is going on with my ArcGIS and how to fix it. What has happened: everything was ok, I had 10.3 prerelease installed and I was warking with it. I was writting my srcipt ...
0
votes
1answer
36 views

gdal_array.SaveArray() leaves dataset open in Python

When I use gdal_array.SaveArray() to create a raster, the newly created dataset appears to stay open in Python, preventing other processes from working with it. For instance, consider the following ...
1
vote
1answer
20 views

Multiply two lists of raster from two subfolder

I have two subfolders, which contains rasters for each country but which express different variables. I am trying to figure out a way to Loop a multiplication of each raster into a folder with its ...
0
votes
2answers
73 views

Create a script to add delimited text layer in QGIS

I'm trying to use QgsVectorLayer() function to add delimited text layer in QGIS. So I have a txt file (T_1999_1_2.txt) in path: "D:\PATRICIA\DOCUMENTOS\ESTACOES METEOROLOGICAS\DADOS METEOROLOGICOS\T" ...
2
votes
1answer
37 views

Qgis docking plugin - python

I need to create a dock plugin for QGIS using QT designer and Python. I've created a basic plugin in "plugin builder". Then I've changed the .ui so now I dont have standard QDialog box but a ...
6
votes
1answer
120 views

PostGIS polygon edge analysis (orientation, edge length)

I am rather new to the world of GIS and especially PostGIS, so please excuse me if the answer seems evident... I would like to do analysis on a number of buildings. One thing I am interested in is ...
0
votes
1answer
219 views

Cause of ArcGIS Raster Calculator Parsing error <type 'exceptions.SyntaxError'>: invalid syntax?

This is my first attempt at much code in the raster calculator of ArcMap 10.0, but I think I'm close. I have nine rasters (A-I below) and want a new raster with value = 1 where any of the rasters ...
0
votes
1answer
13 views

vector clip based on chronological value

I would like to know if there is any algorithm in python that can clip vector features according to the "date" value? To be more specific the newest date is the dominant value and clipping will start ...