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

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-4
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0answers
22 views

Write a Python script in a single file that implements Haversine's formula [on hold]

A function named haversine which takes all five inputs needed to compute the function and returns the distance between the points on the spherical earth-like surface. It does this by computing the 2r ...
0
votes
1answer
11 views

UnboundLocalError: local variable referenced before assignment wthin model builder iterator in ArcGIS

Within an iterator in Model Builder in ArcGIS I am trying to calculate a field value based on the inline variable substitution. In the picture I have renamed the tools with the corresponding inline ...
1
vote
1answer
19 views

Updating Multiple Fields in Feature Class from a Table

I have a Point Feature Class with 2 million records with 35 fields. I have another csv file (contain 25 fields) which have around 4000 records to update certain records of the Point Feature Class . ...
2
votes
1answer
36 views

Why processing.runalg(“gdalogr:rasterize”…) is not creating out files when running in the QGIS 2.6.0 console?

I want to use the QGIS python scripting functions to turn to rasterize a point vector using many different dimensions. Right now my code looks like this: import processing RasterPixelSize = ...
0
votes
1answer
12 views

How to get layers created in a custom toolbox python script to add to the mxd

I'm trying to create a simple search tool so that my colleagues can easily query a database. My first version is like this. mxd = arcpy.mapping.MapDocument("CURRENT") df = ...
2
votes
1answer
28 views

Arcpy if statement to act on layers at the top level of hierarchy

I am about to save copies of all of the layers in my mxd. I only want to save the top level group layers though. I have some group layers within group layers - I dont want to save them individually. ...
2
votes
1answer
15 views

Odd behavior in a QGIS plugin: my function is triggered twice

I have a plugin with a function (triggered by a button) that selects a specific layer by name, then shows its attribute table. When I close the plugin and open it again, the attribute table pops up ...
0
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0answers
12 views

standard way to write a netcdf4

What is the standard way to write a netcdf4? I'm using this guide http://netcdf4-python.googlecode.com/svn/trunk/docs/netCDF4-module.html but when I dump the output file with ncdump, I get the error: ...
0
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0answers
2 views

how to write a netcdf4 in the right manner [duplicate]

What is the standard way to write a netcdf4? I'm using this guide http://netcdf4-python.googlecode.com/svn/trunk/docs/netCDF4-module.html but when I dump the output file with ncdump, I get the error: ...
1
vote
1answer
29 views

QGIS Modeler flexibility and errors?

I'm trying to build a simple multi-step selection (by attribute) with the QGIS Modeler. I created a simple sample layer to avoid data-driven errors. Now I want to query the layer and select features ...
1
vote
1answer
182 views

How to export a set of layers into multiple PDF(orAI)files, one layer at a time?

I am completely NEW to PYTHON(only took a 3-hr entry course in ESRI tutorial. I have a dataset contains files named as "1_A, 1_B, 1_C....12_A,12_B, 12_c,....200_A, 200_B, 200_C..etc." I need to export ...
4
votes
2answers
121 views

How to run a python script on the server, returning the results to the client

Here's the end result I'm trying for: the user clicks on a feature on an ArcGIS Server JS map a Python script is triggered on the server the Python script uses an attribute from the feature (eg its ...
0
votes
1answer
332 views

visualize bounding box to a polygon

I try to make plugin in QGIS that compare 2 bounding box data, ex: (-32.61442167739459, -32.017601026186576, 13.015663782506067, 13.428145228091406) and (-38.6102467739459, -38.017601026186576, ...
2
votes
3answers
27 views

QGIS python plugin appends values every time it's started

I've written a small python plugin (using plugin builder as base) to simplify the expression process for a given layer (just a few comboboxes that are used to create a query). The combo box populating ...
2
votes
1answer
288 views

Folium GeoJSON Overlay Not Appearing

I am in the midst of a task which involves the clustering of assessment neighborhoods into larger neighborhoods (data link). The goal is build these neighborhoods in a manner consistent with major ...
2
votes
2answers
196 views

Issue while running grass from subprocess

I have a map based web application using geodjango. I needed to display the crime hotspots within a selected polygon area. I found that v.kernel is very good for generating heatmaps/hotspots. So in my ...
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votes
0answers
31 views

How to set NULL value by arcpy.da.InsertCursor on date column?

How to set NULL value by arcpy.da.InsertCursor on date column? I try insert "NULL", None, '', 0 dictIN= [{'field1':"test1",'date1':'01-02-2015','date1':''},\ ...
1
vote
2answers
30 views

Inline variable substitution in Model Builder using python code

I have an inline variable substiution which I would like to import into my Python script. Is that possible? I am trying to make a parameter within my path. My path currently is ...
0
votes
2answers
32 views

Performing batch Join Field in ModelBuilder?

I have a list of 250 feature classes (X1, X2 X3, ...) which all have an individual field that I want to join to another feature class Y. The join can be established through a common field that are ...
5
votes
2answers
740 views

Problem with the where clause in ArcGIS when dealing with variables

I am writing a python script for ArcGIS. I have an input feature class which contains multiple pipelines which is saved as a variable InputPipeline. I would like to iterate through the pipelines and ...
1
vote
1answer
23 views

How to select from selection with PyQGIS?

The expression box has a handy "select from selection" button. Is there a way to emulate this with python? I have the basic expressions down, but can't find a way to do this.
3
votes
1answer
51 views

More efficient way to get the start and the end points of a line (arcpy)?

I am collecting start and end points for a large polyline feature class in a file geodatabase. I am using arcpy, ArcGIS 10.3, Python 2.7.3 64-bit and a 10.3 compressed file geodatabase with just one ...
2
votes
3answers
2k views

How can I fix “ImportError: No module named qgis.core”?

First of all, I'm using Python 2.7.3, QGIS 1.8 (Lisboa) on Windows 7 pro 64 bits. Now let's go to the actual question: I have written some code (Python) that works well within the QGIS built in ...
5
votes
2answers
104 views
+50

ArcPad Checkout from python command line

I have been developing a script to automate my ArcPad checkin/checkout processes. My problem is that I am having trouble getting arcpy to recognize the ArcPad tools from the command line. From the ...
2
votes
2answers
50 views

How to get cell value along Flow Direction

I have: a flow direction raster where I took off (assigned NoData value) the cells that overlayed the river network (from flow accumulation). a perfectly overlapping raster where I asigned a ...
-4
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0answers
31 views

error while trying to compile quantum gis: unresolved external symbol class QwtIntervalData [on hold]

While trying to build qgis-2.6.1 from source on windows 7 32 bit with mvc++ 2008 I got the overall result ========== Rebuild All: 281 succeeded, 3 failed, 0 skipped ========== from this I am able to ...
0
votes
1answer
253 views

Orthographic reprojection with mapnik

I am trying to create a google earth like wep application. My problem is that I can't get to render a full view of the earth. The zoom_all() function generates the following error : RuntimeError: ...
0
votes
1answer
16 views

Shapely (geos) crashes during unary_union

When attempting to union multiple polygons with Shapely 1.5.6 in Python 2.7.9, using GEOS 3.4.2, I get the following error in the underlying C++ code: Assertion failed: (!"should never be reached"), ...
0
votes
1answer
24 views

Collect last word from varied length string for filtering, auto labeling and column population? [on hold]

I have been looking and reading for a few days about how to collect the last word from a varied length string. I have found lots of postings about how to collect/split the last word, but none of the ...
1
vote
0answers
29 views

If Else Statement Existence of a File With User Input [on hold]

I am trying to design a block of code that checks if a user inputted directory exists, prints if it does, and if it does not. import os foldername = raw_input ("Please enter the name of your ...
3
votes
1answer
342 views

Configuring spatialite database access for Python 2.6.6

I'm working on a GIS project, and I would like to implement and test some geo-spatial algorithms in Python. For this purpose, I will not only need sqlite, but also spatialite, in order to store and ...
0
votes
0answers
47 views

gdal ReadAsArray returning NoneType

I'm trying to read in several rasters as array using gdal in a python script, but I keep getting NoneType returned and can't figure out why. The process is this: 1. Use gdalbuildvrt ...
1
vote
1answer
43 views

How to get a layer by name in PyQGIS?

I have a plugin which finds buffer for list of cities, provided the distance. The state and city names are taken from the attribute table and gets filtered accordingly. What I want is My plugin should ...
-1
votes
2answers
134 views

arcpy calculate string field: Any ideas what how to fix this?

I'm trying to store a string value obtained from a loop through a tuple into a field called ROW_1. The code goes like this: for creekclass in listOfClassTuples: (classname, Permanency, ...
0
votes
0answers
19 views

Suppress values from multiband rasters

I have a raster stack with 84 bands . It is a time series raster. It so appears that the cloud is causing error in my processing and hence i need to suppress or replace them by a NaN to eliminate them ...
0
votes
1answer
24 views

ImportError: libqgis_core.so.2.9.0: cannot open shared object file: No such file or directory

I installed qgis in debian linux and I want to run a standalone app in python. So I import qgis.core and qgis.gui in this app. But it gives me an error: ImportError: libqgis_core.so.2.9.0: cannot ...
2
votes
1answer
134 views

AttributeError with unicode object 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 ...
5
votes
1answer
403 views

QGis Zonal Statistics Plugin NoData included in Calculations

I have been trying to use the QGIS zonal statistics plugin. My raster has a nodata value of -99999 and all other values are positive. After computing the mean zonal statistics there are a number of ...
0
votes
1answer
51 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: ...
20
votes
11answers
4k views

What are the Python tools/modules/add-ins crucial in GIS?

With ArcGIS 10, Python has become the de-facto scripting language for ESRI. While leading Open source software like QGIS, GeoServer, PostGIS all supports Python. Thus it became important to know/learn ...
2
votes
5answers
115 views

How to export attribute table with start and end coordinates of lines to Excel?

I am working in QGIS. I have a georeferenced line layer and I want to export the attribute table and the coordinates of start and end points of my lines to Excel. Can I do this with QGIS?
0
votes
1answer
217 views

Spatial ETL Tools won't run “AttributeError: 'module' object has no attribute, etc.”

I have a python script that runs 5 Spatial ETL tools that I wish to run as a scheduled task. Each of the tools will run successfully from ArcCatalog and also from the ArcCatalog Command line. If I ...
6
votes
4answers
459 views

Migrate in a new programming GIS language

The last five years I have been working with VBA and ArcObjects for developing a specific application within ArcGIS. That project that began around 2008-2009 carried out with VBA and ArcObjects which ...
1
vote
2answers
140 views

Adding layer into ArcMap via Python - .pyt versus .py

In the final step of a script I've built, I'm trying to add a layer into an empty blank map document. This is my block of python code below that adds the layer. Everything works fine if its run from ...
5
votes
2answers
580 views

Load and display a layer from SQL Server using PyQGIS

I'm having a go at using pyqgis from within the QGIS python console to load a layer from SQL Server and display it. I feel like I'm part way there but I'm having a real issue getting the layer to ...
0
votes
1answer
47 views

Is it possible to embed python in code for HTML pop-ups in ArcGIS

When clicking a point feature I want the html pop-up to not only contain the data of the feature but also an image of the area around the feature (eg. 2 km^2). The image would have the base map 'World ...
1
vote
2answers
148 views

Why is my cursor empty?

Yesterday I set up a Python script using a cursor on a layer. Today I've tried running again and no matter what I run it in, the cursor is empty. I've tried removing the query on the layer, tried ...
7
votes
2answers
2k views

How to get raster corner coordinates using Python GDAL bindings?

Is there a way to get the corner coordinates (in degrees lat/long) from a raster file using gdal's Python bindings? A few searches online have convinced me that there is not, so I have developed a ...
2
votes
1answer
24 views

Python FindLabel Function for Label Expression with Formatting Font?

I originally had this FindLabel function (which works)... def FindLabel ( [NAME], [Count_] ): if [Count_] != None: return [NAME] +'\n' + "Well Log Count: " + [Count_] I wanted to format the ...
0
votes
1answer
31 views

Cannot rename output file using standalone script for QGIS

I would like to rename all output files after my script has finished processing them by adding "(A)" after their file name (eg. Layer.shp -> Layer (A).shp). I received an answer from this post on the ...