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

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1answer
89 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 ...
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1answer
31 views

PyQGIS: How to send signal to call unsetMapTool()

I've created a map tool to add some functionality to adding point features in QGIS 2.0. I'd like to unset this map tool if editing has manually been terminated by user. I've attempted as shown below, ...
0
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1answer
25 views

Add attributes to an output shapefile schema (via meta)

I am trying to copy the schema of an existing shapefile and add to it in an output shapefile. Somehow I am not getting anywhere with this...though the docs seem very clear (and the download page : ...
2
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2answers
53 views

GetCount raises exception

I opted to use gp.GetCount in my script. This raises an exception, though the process completes "successfully" while returning zero features (which is untrue). I'm wondering how this could be. Using ...
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0answers
30 views

How to get QGIS to play with pandas (Windows)?

has anybody been successful getting pandas to work with QGIS's Python installation, on Windows? I've used the OSGeo4W installer to install QGIS2.2, which comes with Python 2.7 and Numpy 1.5.1. Any ...
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40 views

Error: Algorithm not found

I wrote the following code to start using QGIS APIs. in a very short script seen below, the "Error: Algorithm not found" is thrown and "print processing.alglist()" is showing none. Any idea why this ...
0
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3answers
107 views

Using ArcPy and Python to export Table View as PDF format?

I am using ArcPy to select from a layer and display the result on map as a table view. Now I want to export the table view as a PDF format. Anybody know about it? If it is beyond ArcPy to export ...
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0answers
55 views

PyQgis: How can I “append” features to a Vector Layer instead of “stacking” them?

As I read data from a text file and add points to a QgsVectorLayer (as well as related attributes), each new record gets 'stacked' on top of the previous one in the Attribute Table (and within the ...
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2answers
49 views

Issues Reading a table from Geodatabase

I have scripted a process to read a CSV file into a file geodatabase. Then, I want to read this imported file and work on it by adding new fields and calculating values. However, while using the ...
0
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1answer
73 views

Automating Intersect between two polygon layers

I have a spreadsheet that has county-level occurrences of around 1000 species within the US in the column headings (Species State County). Thus, for some counties there may be multiple species. I ...
1
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1answer
59 views

Iterating over selected features in QGIS Processing

I used to be able to iterate over selected features using the following script in v2.0. import processing features = processing.getfeatures(layer) for feature in features: #Do whatever you need ...
2
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0answers
51 views

How to detect turns of a route?

I'm doing a Python simulation of a vehicle, driving along a specified path. I generate dummy GPS readings, that fetch the current position of the vehicle, with some randomized error added. After a ...
0
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1answer
41 views

Blank Shapefile output?

When executing the following command string in the active browser, Qgis projects the triangle polygon and associated attribute table correctly. Upon reopening the shapefile in a new browser, the ...
1
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1answer
49 views

How do you determine when user is clicking the end point of an edit sketch using ArcObjects?

I am using vb.net working on ArcObjects. One requirement is to pop up a toolbox once the user click the end point (double click the point under editing status). So I want to know how can I know when ...
0
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1answer
53 views

Programmatically set layer properties Python Init function

Is it possible to set the layer properties Python Init function field programmatically? I've been looking through the qgis 2.2 api but can't seem to find anything on it. Hint, suggestions and ...
2
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2answers
99 views

Calculate Slope Between Pixels Through Time: A Time Series Trend Analysis

I have a 9 year weekly time series (~500 raster grids of equal cell size and extent). I'm interested in obtaining the regression line slope between pixels (Imagine stacking all 500 grids on top of ...
2
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1answer
125 views

How to surround a Polygon object with a corridor of specified width?

I'd like to build a corridor surrounding a polygon, so that the corridor's outer bounds all have the same distance to the inner bounds. Like this: I've made this lousy graphic in Paint, since I ...
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0answers
45 views

Highlight paths between two points

I'm new to qgis and very sorry if this is a simple question to ask. IS there a way to highlight the available paths (roads) between two selected points in a road map(in qgis) ? I want to find the ...
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0answers
35 views

QGIS Python API: SAGA difference algorithm does not split parts

I am using the QGIS Python API in an external script (platform: ubuntu). Everything works as expected. But when I am using the SAGA difference algorithm within the script, there is an issue. The ...
1
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1answer
51 views

Import error when utilizing QGIS's Python Init function

Based on the answer to Referencing Qt UIs external to plugin with python. I'm trying to utilize the "Layer Properties / Fields / Python Init function" to execute a file (test_file.py) that is located ...
2
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0answers
38 views

How to add nodes into graph

I'm new to qgis and in here I want to find a path between two selected points on the map(Roads-vector layer). The points are selected by the user, using mouse clicks. So here I used the astar ...
2
votes
1answer
49 views

FME - Use Python Caller to Set Search Envelope in Another Workspace

I have an FME workspace which has a number of different workspaceRunner transformers. The first workspaceRunner launches a workspace which buffers a pipeline and outputs the bounding coordinates to a ...
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0answers
48 views

QGIS API changes from 2.0 to 2.2

I have the same program running on two different machine, one with Qgis 2.0 and the other Qgis 2.2. The machine running 2.2 doesn't seem to render the map canvas. I thought it was how I has creating ...
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0answers
20 views

'QgsGraph' object does not support indexing

Traceback (most recent call last): File "/home/kasun/.qgis2/python/plugins/floogin/floogin.py", line 246, in findRoutes path=self.astar.astarSearch(graph, start, end) File ...
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0answers
43 views

Draw polygon shape via Qbutton

Ideally; a Ui Qbutton is needed that will activate map canvas editing to add a polygon via the classic mouse click rubber band method. Upon a concluding right click with the active tool, editing ...
0
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1answer
51 views

In arcgis10.2, can I access arcobjects using python? [duplicate]

I am using python in Arcgis 10.2, but it seems Python cannot meet all my developing demands, from the forum, others recommend to use python to access arc objects,but what they mentioned is the old ...
0
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1answer
105 views

AttributeError: 'int' object has no attribute 'save'

I am trying to use a conditional statement to generate a raster with binary values from a raster with probability values (floating point raster). This is easily done within ArcMap by batching the ...
3
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1answer
62 views

Python MemoryError when running ArcGIS Python Toolbox tool

I have a Python Toolbox (.pyt) containing a single tool. Part of that tool is the following function, which creates a dictionary from an attribute table, where the keys are the rows' OBJECTIDs and the ...
3
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2answers
140 views

How do I know if I am running 64-bit background geoprocessing on ArcMap 10.2?

I'm running ArcMap 10.2 and just set up 'ArcGIS for Desktop Background Geoprocessing (64 bit)' and now I have both the ArcGIS10.2 folder and ArcGISx6410.2 folder inside my python folder. I have ...
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1answer
38 views

Reinitialize ArcGIS10.0 Python installation

I am developing a Python script for a Toolbox that required a few libraries which I installed manually into C:\Python26\ArcGIS10.0\ and it worked just fine. To make the distribution easier, I dived ...
1
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1answer
35 views

How to covert gridded (gnomonically projected by distance) data to lat/long data

I have a grid of data that is in a gnomonic projection, centered on a lat/long point (WGS-84). The grid has a 1km spacing. Given this I can easily obtain the x,y coordinates/distances from centre ...
3
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2answers
49 views

FME - Conditionally make parameters visible

I have an FME workspace in which the user sets several parameters before running. The first parameter is a multiple choice where the user selects which layers they would like to process. Depending on ...
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2answers
34 views

FME - Filter Parameter choices to only projected coordinate systems

I have an FME workspace in which the user sets several parameters before running. One of the parameters is a Coordinate System. I would like the user to choose only Projected Coordinate Systems as ...
0
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2answers
38 views

Can't get dataProvider object outside of QGIS python Interpreter

Within PyCharm import qgis.core as qgis vector_lyr = qgis.QgsVectorLayer("Point", "distance nodes", "memory") pr = vector_lyr.dataProvider() print pr prints None Within Python Interpreter in QGIS ...
0
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1answer
55 views

Howto create complex polygon with pyshp

using the pyshp library (https://code.google.com/p/pyshp/) I am trying to create a "complex" polgon with one hole inside the main-poly plus one island-poly. It should look like this: I used the ...
0
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1answer
72 views

Iterative raster calculation script using NumPy arrays breaks after ~10 rasters, returns: “TypeError: Cannot create raster for numpy array.”

Here is my code: #Generate Cumulative Thresholds #5/15/14 import os import glob import arcpy import numpy as np #Enable overwriting output data arcpy.env.overwriteOutput = True ...
1
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1answer
43 views

Calculating average of 3 fields where nulls are present

I have created a new field to calculate the average of 3 other fields in a table where nulls are present. Using python as the parser(with no code block) I used this: (!Slope_PCT! or 0 + !Flood_PCT! ...
0
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1answer
74 views

How to create a grid after merging shapefiles?

Follow up question to QGIS Model Builder Script - Possible to merge layers in a folder? I think I'm missing something very obvious here but can't seem to find it. After merging shapfiles in a folder, ...
1
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1answer
39 views

How to count the number of entries a user has selected in a multivalue field of a tool dialogue using Python and ArcGIS 10.2.1

I am currently creating a script that will read data in one (to many) Excel spreadsheet(s) and would like to know how to get a count of the number of spreadsheets entered by the user. The script will ...
0
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0answers
48 views

gdal commands cannot import gdal — possibly ArcGis conflict with separate Python?

I installed ArcGIS 10.1 yesterday (Windows 7 64-bit), but have a separate Python 2.7 installation. Now my gdal does not work correctly anymore. It looks like all commands without the ending "*.py" ...
0
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0answers
30 views

Running algorithm from Processing takes much much longer time than doing it from Qgis GUI

I have a road layer with 32000 features, and I want to find all the intersections. when I use processing->SAGA -> convert polygon/line vertices to points, it is all done in less than 5 seconds. ...
1
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1answer
65 views

Raster calculation in for loop returning exit code -1

I've put together a python script that does some calculations on rasters by converting them to NumPy arrays, doing the math, then converting them back to Raster and applying all the same spatial ...
0
votes
1answer
100 views

ArcGIS 10.2.1 Table To Table tool in Python script gives ExecuteError: ERROR 001156?

I work for an organization that just upgraded from esri arcmap 9.3.1 to 10.2.1 and I'm currently in the process of updating the python scripts. When running a script I'm getting hung up on a portion ...
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0answers
24 views

QgsFeatureRequest and QgsVectorLayer are missing in the QGIS

I am trying to use part of my friend's code in eclipse written in Python using QGIS APIs. I have installed the QGIS 2.2.0. now before running the code, it seems that something is missing here. All ...
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1answer
92 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 ...
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1answer
42 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 ...
0
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1answer
39 views

Changing $id in a shapefile in QGIS

I need to change the id (feature.id() in the python API or $id in the field calculator) of for features in shapefile layers in qgis, and I need to do it in Python. Is there a way? I tried something ...
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0answers
25 views

Using GDAL and Python to replace the Spatial Analyst TabulateArea method

Has anyone tried to phase out the use of ESRI's Spatial Analyst extension by replacing it with GDAL in Python? I have a script that only uses the TabulateArea and Statistics analysis but not much else ...
1
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1answer
82 views

ToolBar icon images missing

very early build ~ zip file I am getting blank outputs for button images in a custom toolbar. Although the button information populates the dockable toolbar, they lack respective icons [see Fig.1] ...
0
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1answer
63 views

QGIS Model Builder Script - Possible to merge layers in a folder?

I would like the user to select a folder via the interface in which all the vector shapefiles inside that folder would be merged. I have been using the Model Builder and looking at example scripts ...