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

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2
votes
2answers
186 views

Conditional field calculator expression

I need to calculate the PIPEID field to equal the G_KEY_COMP field if PIPEID is null or PIPEID and G_KEY_COMP do not match. I think the first condition of the PIPEID being null is covered by the ...
2
votes
1answer
2k views

How to convert Python (ArcPy) script into tool or toolbox script?

I've written a simple python script that allows me to quickly create a copy of a template Mxd, pointing to different shapefiles. The user specifies the new location, a name for the new mxd, then the ...
3
votes
0answers
635 views

Why does the QgsVectorFileWriter have probelms creating vector files? [closed]

I am using QGis 2.0.1 and have tried to create a new GIS feature file (SQLite, Spatialite, and Shapefile) of a subset of the data. I am then saving a copy of the style of this layer and applying it to ...
1
vote
1answer
598 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 ...
0
votes
1answer
79 views

Retrieve path of running plugin in QGIS

In my plugin's directory I've got some XML settings files that I'd like to parse at a particular point during execution of the plugin. Is there a way to get the absolute path where the plugin's .pyc ...
6
votes
1answer
6k views

Shortest distance from point to line (big dataset)

What is the best method to calculate the distance from the nearest road for a series of address points in QGIS, having a very big dataset? (QGIS 2.0.1, Win XP) I read the answers to previous similar ...
11
votes
2answers
1k views

Is there a way to refresh imported modules in a ArcGIS Python Toolbox?

When using a python toolbox (.pyt) in ArcMap, I'll typically follow a pattern where the .pyt file itself is simply a wrapper to collect input arguments and define the tools themselves. Supporting ...
1
vote
1answer
86 views

Extract information of a raster overlayed on another raster with a lower resolution directly in python

I have two aligned rasters with the same extent, one has a resolution of 5 meters and the other of 125 meters. I would like to place the 5 meter one over the 125 meter one and assign to these smaller ...
0
votes
1answer
37 views

whereClause syntax for Cost Distance parameter

I am looking to create a sql expression regarding point feature class and selection based on 'Name' field to pass to arcpy.sa.CostDistance() param[0]. similat to: savepath = env.workspace = ...
0
votes
1answer
676 views

How to generate jVectorMap for United Kingdom (UK)?

I have shapefile for UK , i need to convert this to the jVectorMap Here is my script python ^ converter.py ^ ./shapefile/map.shp ^ ./output/jquery-uk.js ^ --width 400 ^ --where "ISO = ...
2
votes
0answers
116 views

Compare line with next line in attribute table shapefile

I am making a python code for ArcGis 9.3. The aim is to compare the value of my field "ID_BV" at line l with value of field "ID_BV" at line l+ 1. And depending of the test answer i populate another ...
1
vote
0answers
198 views

model to connect points with line and set the digitize direction according to height

I'm trying to develop a tool that connects a point layer (manholes) with lines (waste water pipes) and sets the line direction according to an height attribute acording to gravity(from high to low). ...
1
vote
1answer
343 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
736 views

QGIS Map tools and Map canvas--QString errors

I'm trying to learn more about using QGIS Map Canvas widgets and creating custom map tools, so the information from the PyQGIS cookbook is very helpful. After trying to experiment with mywnd.py from ...
1
vote
1answer
195 views

empty file geodatabase error (nowhere feature class)using arcpy [closed]

i want to import a python(2.7) script to arcmap 10.1 my script has 2 inputs variables one for workspace and another raster dataset and i want o convert input raster as feature class polygon . i want ...
0
votes
2answers
94 views

Output of RasterToPolygon not supported as shapefile

I made a python code for arcGis 9.3 which do the following step : 1) Convert all the raster (.tif) in a folder to polygon shapefile in another folder 2) Intersect all the converted ...
2
votes
0answers
446 views

Editing QGIS point layer: retrieve attributes of intersecting line layer

I'm creating a custom editing form using QGIS 2.0 and would like to modify the mouse event when creating a point. I've gotten a start by reading this thread: How to programatically check for a mouse ...
3
votes
2answers
1k views

What's wrong with my IDW interpolation function (Python)?

Original Question Can anyone see what's wrong with my custom IDW interpolation below? I know there are existing libraries that can do this for me, but for various reasons including educational and ...
5
votes
1answer
525 views

QGIS - Changing Legend Size with Python

In QGIS, I use the python console to generate image files through the composer. In particular, I am creating a map with a legend. The legend is too big. It occupies about 1/8 of the image. I would ...
5
votes
1answer
144 views

Is there a tool to track edits that were made?

Is there a tool/report that keeps track of what edits were made that I could run prior to or after reconciling my versions? This would help me to know if there are any changes I need to make to any ...
0
votes
1answer
153 views

gdalwarp from within python script misbehaving

I'm trying to run gdalwarp from within a python script start = "gdalwarp -overwrite -ts 22 20 -r average -srcnodata 99 " input_file = filename[12:] output_file = "temp1.tif" print ...
3
votes
2answers
845 views

Add row and column name to square grid feature in ArcGIS

I have a square grid feature class of 250 x 250 tiles. This will serve as a tile index for a a project. They currently have no identifying attributes other than a unique ID. I need to add a field ...
9
votes
1answer
634 views

How to split two interscting polygons by the average linestring of the shared area (QGIS / python shapely)

I have two polygons, POLYGON((-5 -5,-5 5,5 5,5 -5,-5 -5)) POLYGON((1 1, 1 7, 7 7, 7 1, 1 1)) and wish to split them evenly. The result should be a split along the red marked line. I'm using ...
2
votes
3answers
2k views

Adding a new field and calculating area using Python

Using Python, how do you add a new field to your shape file and calculate the area in km2?
1
vote
1answer
300 views

How do I use ogr2ogr with python GDAL? [duplicate]

I've just installed GDAL, but I don't know how to import/use ogr2ogr. I've tried: from osgeo import gdal from osgeo import ogr and searched both for ogr2ogr, but it wasn't there.
-1
votes
1answer
60 views

define error for python script to import arcmap [closed]

i want to create a simple python script for create one file geodatabase but show me define error # Import arcpy module Import arcpy import sys import os from arcpy import env from arcpy.sa ...
0
votes
1answer
210 views

Better ways to check if GRASS r.water.outlet works out fine output

I use my python script to call GRASS module r.water.outlet from outside, and here's my script(I perform this script in pyscripter): import os import sys #set up GRASS environment variables ...
8
votes
1answer
3k views

What Lidar processing tools are available in Python?

I have been using FUSION and the command line FUSION Lidar Toolkit (LTK) to process Lidar data. A broad Google search ("Lidar Python") yielded libLAS and pyLAS as Python lidar libraries, however, ...
0
votes
0answers
255 views

No data appears when using gdal_calc.py but source had data values

I'm in the process of calculating topographic exposure using a mix of GDAL, grass, R and python in Windows. I need to process a very large tiff file using the following calculation: ...
0
votes
1answer
341 views

registering or unregistering as versioned a future dataset with python

As you know, you can store feature classes in arcsde in two ways. Firts, in the root path: sde_conn_file.sde/FeatureClass Second, in a dataset: sde_conn_file.sde/DataSet/FeatureClass How can I ...
1
vote
0answers
405 views

Running python script outside of Arcmap's python console

My codes works fine in Arcmap's python windows. But when I try to run it in a command promt windows, It says that; ERROR 000837: The workspace is not the correct workspace type. But it works fine ...
1
vote
1answer
63 views

GeoDjango Scale/Layers issue?

I've been having issues visualising data from a shapefile in GeoDjango using OpenStreetMaps. I believe it's some sort of a scale issue because of how it appears(as you can see in the screenshot of the ...
0
votes
1answer
142 views

Layer relations via Python

Is it possible to, through Python, to create the relations that it's possible to create in Layers/Properties/Fields/Relations, and if so how? I first thought these were saved in the styles, but that ...
-2
votes
2answers
6k views

How to avoid ImportError: No module named arcpy causing Failed to execute (Script) error?

I have a proplem with arc hydro in arcpy,i want to create a simple script where automated some tools from archydro in arcpy.. I use arcmap 10.1 and python 1.7,my import is one dem and my export is a 6 ...
1
vote
0answers
260 views

How to use GDAL on Heroku?

I have a geospatial python app that I want to use on Heroku. This is my requirements.txt file: Flask==0.10.1 Jinja2==2.7.2 MarkupSafe==0.19 Werkzeug==0.9.4 gunicorn==18.0 itsdangerous==0.23 ...
2
votes
2answers
806 views

Fiona: get each feature extent (bounds)

I was looking in Fiona to get for each feature its extent but I didn't find how. I have try to far to do something like below import fiona with fiona.open('countries/ne_10m_admin_0_countries.shp', ...
2
votes
2answers
765 views

Mask image based on no-data pixels in another image with different projection - GDAL or Python

I've got a land cover image which covers the whole globe, and a satellite image which covers a very small part of the globe. These two images have different projections, co-ordinate systems and pixel ...
0
votes
2answers
107 views

ArcPy symbolize layer if a value is correct

I want to symbolize a layer in an active session and add to display if some kind of value is right. I found a way to symbolize in an active session here So i tried to extend it, but unfortunately it ...
2
votes
2answers
3k views

How to plot geoJSON using Python?

I have huge geojson file that I am working on: [{ "geometry": { "type": "MultiPolygon", "coordinates": [ [ [ ...
1
vote
0answers
63 views

Add a raster specifying the projection in pyqgis

I would like add an raster but I want to specify the projection. If I do : qgis.utils.iface.addRasterLayer(url,layerName) QGIS ask me to specify the projection. I want to this with python. How I ...
2
votes
4answers
727 views

How to turn all lines into one direction?

How can I turn all features of my polyline (postgis and/or shapefile) into one direction - it doesn't matter what direction. I know how to switch the direction of lines but I have no idea how to ...
1
vote
1answer
612 views

Equivalent function to shapely's envelope in ogr?

I wrote a very simple python function that gives me the envelope/bounding box/...based on two coordinate pairs (ower left and upper right corner): # ... def get_bounding_box(self, ll_corner, ...
1
vote
1answer
361 views

What do “count”, “mean”, and “sum” in QgsZonalStatistics mean?

I am working with Qgis and making some analytics of lightdata. I've used these commands: rasterfile = qgis.utils.iface.mapCanvas().currentLayer().source() vectorlayer = ...
6
votes
1answer
445 views

Determining Shape Area Field Name

I'm dealing with a varierty of spatial polygon files (shapefiles, file/personal gdb feature classes, sde feature classes (some with spatial views)) and depending on the file type, I get a mulittude of ...
0
votes
1answer
137 views

Move features from one layer to another existing layer

How can I move Selected features from one layer to another existing layer? I have tried Copy (Data Management), Copy Features (Data Management), But I got the error: ExecuteError: ERROR 000258: ...
0
votes
0answers
250 views

Mac QGIS 2.2 error executing Python code

Newbie Using QGIS version 2.2 with Python 2.7.5 on OSx 10.9.2 Getting the following error. Any idea on how to resolve? I'm not sure if it has ramifications on the display of the Google data. An ...
0
votes
0answers
63 views

Delayed moving average

I want to develop a plot of delayed moving average. The code for this in MATLAB is: nr_pontos = 36; coefs_filtro = ones(1, nr_pontos)/nr_pontos; data_dma = filter(coefs_filtro, 1, data); ...
0
votes
1answer
79 views

Selection/Deletion of all smaller polygon/s in a SHP - Python solution?

ArcMap 10.2 user, with Spatial Analyst only. No ArcServer or of sort. I have abt 500+ polygon shapefiles, each containing 2 or more polygons. All of them has a NAME column and the rest of the ...
9
votes
2answers
1k views

Python, GDAL and building raster attribute tables

I have an integer raster for which I would like to build a raster attribute table using Python and GDAL. I can create a GDAL raster attribute table in Python as follows: >>> rat = ...
1
vote
2answers
163 views

Suggest an algorithm to measure how a node is connected to road network

I try to measure how well a node is connected to the rest of the network. If a city has a distant suburb connected with one sole road, it's connectedness is, say 1. If it's connected by 2 roads, it's ...