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

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1answer
866 views

Where Clause problems when all parts are user input variables

I have written some generic user ipnut code for a toolbox script (ArcGIS 10.0) but because everything is a variable I don't know how to write the SQL whereclause. Please can someone help and suggest ...
1
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1answer
96 views

python scripts for accessing info from a postgresql database in case of a qgis application?

I am beginner and I need to know if I could access a postgresql database from python script made for a qgis application
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2answers
306 views

extract edge of a line of a vector layer in a new point layer [closed]

I'm using python to build a plug-in in Qgis. I need to extract the edges of each line feature of a vector layer to create a new point layer of all edges. Someone can help me? My data input is a vector ...
0
votes
1answer
73 views

How to Add Field Between Two Existing Field in Shapefile

Can you please let me know if it is possible to add a new Field between two existing field using ArcPy? For Example if I have "Name", "Area", fiels already in my shapefile can I add a new field called ...
3
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2answers
733 views

Create point geometry in a feature class with all the attributes prepopulated

So here is the problem. I have a text file with space delimited values. A standard text file with the headings separated by spaces and then on each next line values for these headings (columns) also ...
3
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1answer
316 views

How to apply a color gradient to a shapefile from QGIS console?

Anyone knows how to do a color gradient from the console to a shape file in Qgis (orin Python)? Like the image below.
3
votes
3answers
1k views

Formula for coordinates (lat, lon), azimuth and distance.

I would like to know how to find a set of coordinates on a small circle some distance from another point. For example, lets say A = (39.73, -104.98) #Denver B = (39.83, -106.06) #point ...
3
votes
3answers
265 views

How to convert Midpoint of Polyline into Point Feature using ArcPy?

I am trying to write a python script to determine flow direction on a water pipe network. I've used this script to find the mid point along each polyline, now i need to convert this data into a point ...
0
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1answer
409 views

Better way to handle HDF and GeoTIFF files

I am using GDAL and MODIS reprojection tool in my python project and want to know better way for math new indices of HDF data (MODIS data). Also I want to visualize them in web. Which format is more ...
0
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1answer
345 views

Python: Using re and update cursor over three columns [closed]

I'm working on this code and got a little to excited...only to find out it wasn't perfect! I'm trying to eliminate the suffix (row1) of roadnames(row0) and parse just the roadname to a new ...
8
votes
4answers
5k views

How to convert geometry to WKT using ArcPy?

I would like to be able to convert a single feature (or potentially many features) in an ArcGIS layer into Well Known Text (WKT) format during a geoprocessing operation using Python and ArcPy (no ...
5
votes
2answers
587 views

Is there a way to auto-update symbology between .mxds for the same shapefile? (Python?)

I have a variety of .mxds for any one project I'm working on, which are all different but all use the same set of base shapefiles for my project. I know I can save a .lyr version of my initial ...
1
vote
1answer
249 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 ...
3
votes
3answers
3k views

How to batch clip to single-part shapefile using ArcGIS 9.3 and Python 2.5?

How do I clip a shapefile to a single-part shapefile using ArcGIS 9.3.1 and Python 2.5? Example: I have a set of lines (lines.shp) I am trying to clip to each record in a shapefile called Grids.shp ...
7
votes
1answer
444 views

Draw middle ordinate perpendicular to chord, out to curve, with arcpy

I've been assigned to find the radius of road curves. My boss found this article describing a pretty straightforward method of doing so: find the start/end points of the curve; create a chord; ...
7
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3answers
2k views

How to Receive an Email after a script has run?

I'm working my way through my first attempt at scheduled tasks with modelbuilder and python. So far I have: Created a model that reconciles our SDE versions and then compresses the database. ...
11
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3answers
1k views

How to convert LAS file to numpy array?

I have begun learning how to manipulate LAS data in python and wanted to see how others handle LAS files. I would like to read the points (I am using a numpy array), and filter out classes 1 and 2 ...
5
votes
2answers
576 views

How do I get the projection of an LAS file using liblas?

I am using the python api of liblas to read/write las files. I would like to get the spatial reference information of the las file using liblas, but have been unable to figure it out. Can anyone ...
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0answers
77 views

Loading QGIS and files from Python's use of os.system?

I am trying to open QGIS and load two files using the following code in Python: os.system('qgis D:\data\vector.shp D:\data\raster.tif') However it returns this error message: 'qgis' is not ...
1
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1answer
205 views

Polygons not appearing when creating shapefile based on criteria using GDAL and Python (area calculated properly)

I am looping over the features of a shapefile containing multiple polygons. If certain criteria are met, I want to save the current feature in a new shapefile. I am doing this using GDAL 1.10.0 with ...
1
vote
1answer
313 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
668 views

using GDAL/python to stack georeferenced images of different sizes

I am in the process of porting a code I wrote in IDL (interactive data language) to python but am running into a bit of a problem that I am hoping someone can help me with. The code goes like this: ...
5
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1answer
709 views

Create point between two points with given distance or length

What I have: Coordinates of Point A and Point C and therefore vector and azimuth from A to C What I want: Coordinates of Point B (between A and C) with a distance from A to B of 35.2 meters. ...
0
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1answer
869 views

Finding differences between two shapefiles in Python

I'm trying to find out whether there were any border changes between two yearly shapefiles. I've heard a lot of praise for Python's open source GIS tools like Shapely/Fiona, and thought I would try ...
0
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1answer
3k views

How to set PYTHONPATH in OS X to use PyQGIS?

I am trying to use PyQGIS in custom applications. I am on Mac OS X 10.9 with QGIS 2.0.1-Dufour. I know I have to set the the PYTHONPATH environment variable. This is the path to QGIS on OS X: ...
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1answer
462 views

Convert measurement geometry from ground reference frame to satellite reference frame

I need to convert solar_zenith_angle, solar_azimuth_angle, platform_zenith_angle, and platform_azimuth_angle from a reference frame at the WGS84 surface to a reference frame at the satellite observer, ...
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0answers
63 views

Why legendLayerActions is not available in QgsLegendInterface

There's a reason why QgsLegendInterface (the python interface to QgsLegend) doesn't expose: QList< LegendLayerAction > QgsLegend::legendLayerActions( QgsMapLayer::LayerType type ) const method? ...
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0answers
178 views

How to run PostgreSQL stored procedures from QGIS? [closed]

I'm trying to figure out if it's possible to run a stored procedure in a Postgres database from QGIS, more specifically I would like to do this from within a python plugin. In this case I'm trying to ...
1
vote
1answer
958 views

Insert Cursor fails to write results to table

Insert Cursor fails to write results to table. The Search Cursor is returning the results, but errors when trying to insert into field. # Insert Cursor for GDB table to GDB table # Import modules, ...
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0answers
86 views

Populate a new field with list of the top 5 values of all fields for that record

I have 15 fields. I would like to add a new field that is populated with the field name and value of the top 5 highest values of the 15 fields for each record in the table. The new field would be a ...
1
vote
1answer
236 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 ...
6
votes
3answers
635 views

How to Run Viewshed on one feature at time in shapefile?

I have over 100 features in a shapefile and I want to create individual viewsheds for each and then run processes on each of those resulting viewsheds in ArcGIS using Python. Is it possible to write ...
6
votes
1answer
1k views

Why close a dataset in GDAL Python?

I see quite often in Python GDAL code that people close datasets at the end of their script. Why does it makes sense to close a dataset in Python GDAL? Are there any consequences if I don't do it? ...
5
votes
2answers
2k views

Are there Python packages for Landsat 8 processing?

While there are a number of python projects for MODIS acquisition and processing (pyModis and get_modis), I have yet to encounter a toolset for automating Landsat 8 processing in Python. There's ...
1
vote
1answer
425 views

Map Layout Elements In New Layer Automated Using Python

I was wondering if there was a way to put a title and integer data from an attribute table in a new layer created in Python. I was able to create a new layer using copy features, zoom to the selected ...
2
votes
1answer
430 views

Getting SAGA-GIS Python Bindings without compiling from source

I am very new to SAGA-GIS, but I recently developed a workflow using SAGA for processing LiDAR data. Now I need to batch the process using Python. I installed SAGA from the Windows installer and I ...
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0answers
592 views

RasterXSize from gdal Nonetype error

I have this code to create a raster file in python: fileInf = QFileInfo(userIntervals) baseNam = fileInf.baseName() rlay = QgsRasterLayer(userIntervals, baseNam) gdalRast = ...
4
votes
1answer
1k views

Select by attribute expression invalid in python

I'm not sure how my expression is failing. Any ideas? inPoints = "points.shp" i = 0 arcpy.MakeFeatureLayer_management(inPoints, "pts") arcpy.SelectLayerByAttribute_management("pts", "NEW_SELECTION", ...
1
vote
1answer
721 views

Why does ListLayoutElements give IndexError: list index out of range?

When trying to create a legend on ArcMap use the following Python/ArcPy code I received an error message: import arcpy mxd = arcpy.mapping.MapDocument(r"E:\cities\MyProject.mxd") df = ...
9
votes
6answers
8k views

ArcGIS/ArcPy Python, how to get latitude and longitude of a projected point?

I have a point feature in a feature class that is being accessed by ArcPy. The point is projected but I need to find an efficient means to get the unprojected latitude and longitude for this point. ...
1
vote
2answers
224 views

Difference between OGRGeometry and Geometry in C++ and python

According to the documentation, there is a python version of OGRGeometry's C++ class (http://www.gdal.org/ogr/classOGRGeometry.html) which is http://gdal.org/python/osgeo.ogr.Geometry-class.html ...
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votes
0answers
197 views

Calculating distances between boundaries of polygons with Python

I have two sets of shape-files which have to be worked on within a Python Script. Those two Shape Files might differ from each other (same thematic content, but 2 different epochs). If there occurred ...
0
votes
0answers
235 views

Change symbology of layer of unique symbol to unique with python

I have a problem concerning how can I change the symbology of a layer with unique symbole to unique values. I don't know how to update it. I used this code: import arcpy mxd = ...
0
votes
1answer
114 views

How can i stop rendering Qgis

In my python plugin ,i select features from a vector layer dynamically using a loop and executing : VectorLayer.select(feature.id()) when i start the loop, the selection become very slow because ...
1
vote
2answers
127 views

Custom BatchProject Script

Here's my problem. My GPS collects data in WGS1984 and I have decided to start working in UTM instead of state plane. Needless to say, I would edit shapefiles, not paying attention to what ...
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0answers
49 views

How to get data from the selected features and embed to a particular featura class

I am trying to write a Python script for ArcMap 10.2. When the user selects some features I want certain data to go to a certain point file. For example, I have a polygon that contains parcel data. ...
0
votes
1answer
149 views

Retrieving raster/coverage width and height in pixels from GeoServer

Is it possible to retrieve the original width and height in pixels for a coverage in GeoServer using either the Python API or REST? I could not find anything in the documentation regarding how to ...
0
votes
1answer
108 views

ArcToolbox model run but warning output in Python

I have created an ArcToolbox and a Model in the toolbox. It uses a lot of Spatial Analyst tools and deals with raster images. When I imported the toolbox in a Python script and ran the model from ...
2
votes
2answers
222 views

How to create simple select script in ArcPy?

I am new to Python and want to create a script inside the ArcMap Python window. My current workspace is a series of rivers portrayed in the state of Ohio. I have a list of fish and the rivers (from my ...
10
votes
2answers
478 views

Can ArcGIS ModelBuilder open Excel file for manual editing, then feed those edits back into model?

I have been tasked with creating a model using ArcGIS ModelBuilder, that initially runs a couple of geoprocessing tasks, before then joining an Excel table to the result of those geoprocesses. ...