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

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6
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1answer
3k views

How to programmatically add shapefile to data frame in Arcmap

I have a toolbox with python script which creates a shapefile from JSON txt file, but it does not show the generated shapefile in arcmap, i have to add it from the output location. What code shall I ...
1
vote
1answer
371 views

Looking for PyQGIS Syntax Examples/Guide

I am a long-time user of arcgis with intermediate experience python scripting for automation of geoprocessing workflows. I am moving towards using QGIS on the regular and I would like to dive into ...
3
votes
1answer
1k views

Iterating through an numpy array and index to a value in another numpy array

I am struggling to get this code to work I want to iterate through an numpy array and based on the result, index to a value in another numpy array and then save that in a new position based on that ...
4
votes
4answers
673 views

How to rename a file in the output (ArcGIS python)?

raslist=arcpy.ListRasters() for ras in raslist: arcpy.ProjectRaster_management(ras,outfolder2+ras+'_Albers',spatialref2) print ras+' has been reprojected' I was using the above code for ...
2
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2answers
69 views

How to travers fields of records without introducing them all in the function?

In my previous question I wanted to reach a field in the field calculation; however, it was pretty easy to introduce a few more inputs for that function. Now, I am facing a problem which needs around ...
4
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0answers
1k views

Finding the “center of gravity” of multiple points where points have unequal weights [closed]

I'm trying to reduce a set of lat/lons (each with it's own weight) into one lat/lon that is the center of mass of all of the points. however when I map the results the average point falls no where ...
4
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1answer
1k views

arcpy “The table name is invalid”

I wrote a script that, ideally, loads raw .las (LiDAR data) files into a geodatabase, then creates a terrain from the multipoint files that are created. When I run the script though I get: ...
2
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0answers
161 views

How can I draw an ellipse filling the dataframe with ArcPy?

I need to modify one of my template scripts to draw a circle from the centre of the (inset) data frame to the edge of the data frame. This will then be used to clip the data frame to shape. I'm using ...
3
votes
1answer
293 views

How to sort features in a layer using OGR/Python?

How can I sort the features of an ogr layer by the values of a field? I tried naive variations of def sortlayer(ds, layer, field): lname = layer.GetName() lsort = ds.ExecuteSQL(b'select * ...
3
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0answers
659 views

How to write vector layer to csv file with geometry by PYTHON?

I use Python try to write vector layer file to csv file with this code QgsVectorFileWriter.writeAsVectorFormat(mylayer, r'c:\temp\xyz.csv', "utf-8", None, "CSV") It can export to xyz.csv but only ...
7
votes
3answers
3k views

Problems setting up eclipse (with PyDev) for ArcGIS 10

I'm trying to use eclipse with PyDev to program in python. In Windows 7 x64, I've added a PATH environmental variable (PATH C:\Python26\ArcGIS10.0\python.exe;) and what I thought were the relevant ...
2
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3answers
693 views

What Python package to use to calculate midpoint?

I asked a question earlier about how to calculate a midpoint. I was wondering if there is a Python library that does this alreay?
2
votes
0answers
141 views

returning exceptions to user via AGS REST

I've got a python script that I run as a standalone and as a gp service in AGS (moving to 10.1 now...). For the standalone execution, I'm throwing a custom exception if there is no data found based on ...
5
votes
2answers
951 views

Why is Shapely not installing correctly?

I am trying to run Shapely on a new machine, and tried both installing it from source, using the installer on its webpage, and using pip install shapely. Every reference I try to make from the library ...
0
votes
2answers
898 views

How to install Shapely, but got stuck into Python language

I have a MAC OSX 10.7.5 and am trying to learn how to use QGIS. Following a couple of tutorials I came to know I have to install shapely. I followed the instructions by the multi-cited ...
2
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0answers
62 views

Is there any way to symbolize a user-supplied input parameter in ModelBuilder?

I have a model built in ESRI ModelBuilder that is run from its tool dialog, where the user supplies the input feature layer that then gets processed in the model. I need the input feature layer to ...
3
votes
1answer
307 views

How to get default parameter value for script tool from csv file?

I am fairly new to python scripting. I have just figured out how to read and write input parameters for a python script from a csv file. Now I am being asked to pre-populate the script tool dialog in ...
3
votes
1answer
686 views

Python coding question, looping through feature classes, AddField, CalculateField, then errors (might be schema lock)

This is not a SDE question. File GDB. Hi, I have a general question on looping through feature classes in a file geodatabase. I have (attached) a python script that adds a ton of fields and ...
0
votes
1answer
254 views

Save longitude and latitude in Django

I had plotted a Javascript gMap.Using the marker,the values of latitude and longitude are displayed.I need to get that values and save it to database.What is the best way to do this and ,How to ...
1
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2answers
182 views

Python select by attribute using a variable counter

I am brand new to python and trying to learn how to do some simple loops but I have hit a snag. Below is what I am working with, I am trying to select the polygon row by row, but I keep getting EOL ...
0
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0answers
22 views

Drillhole Plan Trace in Arc [duplicate]

I'm struggling to find the math to do what I want. I want to plot a top down view of a drillhole in ArcMAP 10.0. I have the beginning UTM coordinate and then for every place in the hole that was ...
1
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1answer
113 views

How to reach a field value of a record in field calculator in ArcGIS 10.1

I have two fields showing number of people in two age groups "young" and "old". these people also live in a cell (point) whose distance to a specific facility is calculated. then I categorized these ...
3
votes
2answers
3k views

How to install the Python module shapely for QGIS use?

I'm using QGIS 1.8.0 on a Mac with OSX 10.6.8 (Snow Leopard). I've installed QGIS including GDAL, GSL, UNIXImageIO, Freetype, and Matplotlib all from www.kyngchaos.com. When installing the plugin ...
4
votes
1answer
1k views

How to use a feature set as an output parameter in a Python Toolbox?

I'm having trouble setting a "Feature Set" output parameter from a .pyt .. I'm using ArcGIS 10.1 SP1. Here’s a short script that can be invoked either from a classic toolbox (thru the main() ...
2
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0answers
76 views

Removing FID as an option from ArcGIS Tool Validation Parameters

I am currently building a script tool which requires the user to select a sorting field from a list (built using a dependency on the featureclass). This Element is working fine, but I would like to ...
3
votes
2answers
5k views

How to convert field values from lower case to upper case in ArcGIS 10.1?

Using the Field Calculator in ArcGIS 10.1, I am able convert the first letter in a value from lower case to upper case. How do you convert the entire value to upper case, though? I can't seem to ...
2
votes
2answers
612 views

Python Code: “Compare two fields and select missing records”

The code I wrote is not right!! It's selecting more than what is actually missing. I think I'm wrong on the matched code line. I need the script to make a list of the "FLAG" field and a list of the ...
2
votes
1answer
232 views

How to store attributes of a large shapefile in a list?

I am trying to store the attributes of a shapefile into a list. With following code it works for smaller shapes: addA = [] While provider.nextFeature(feat): attrs = feat.attributeMap() for ...
3
votes
3answers
1k views

Efficient algorithms to split and join lines?

Referring to the Figure below: How to efficiently join segments into lines? How to efficiently break lines into segments? The above will be applied million times.
1
vote
0answers
221 views

SEXTANTE runalg and QgsVectorLayer issue

I'm trying to make a script for converting polygons to lines. But I'm having some issues while generating temporary layers. In this script, I iterate through all the features of the input layer to ...
2
votes
1answer
280 views

automate color palette generation?

I frequently am in need of color gradients that aren't readily available through ArcGIS or the ColorBrewer add-in. I find the process of manually creating gradients in Arc very tedious: saved custom ...
2
votes
0answers
574 views

Use GDAL/Python to add rasters (tiff) to an ESRI File Geodatabase

I'm using GDAL python to create a bunch of tiff files from a netcdf file. def modelout_to_geotif(netcdfile, outdir, VarName): """ Given the path to the netcdf output, produces geotiffs for ...
1
vote
1answer
775 views

Hotlink vector/raster files to open in current workspace in ArcGIS 10 similar to Mapinfo

I want to add datasets to ArcMap and place them in a particular group layer by simply clicking on hotlinked polygons in a shape file. The same process is easy in MapInfo and I want to implement the ...
1
vote
1answer
455 views

Python GDAL/OGR: WGS84 & meters units

I'm dealing with shapefiles projected in: GEOGCS["GCS_WGS_1984", DATUM["WGS_1984", SPHEROID["WGS_84",6378137,298.257223563]], PRIMEM["Greenwich",0], ...
2
votes
2answers
122 views

How to reproject all featureclasses in a database to another database?

I am very new to arcpy and have ArcGIS 10.0 I would like to make a script where I would only have to change two variables in a script (database_input and database_output) so that I can reproject all ...
0
votes
0answers
364 views

Create a polygon shapefile using point as boundary

Following have two problems: I am now have 4 point in a shapefile and I want to set the point's coordinate for boundary of a polygon The points are xmin, xmax, ymin, ymax that can just be a ...
1
vote
0answers
298 views

Morphometric and hydrological analysis with Python and ArcGIS

How can I write a program using python, that calculates some morphometric and drainage indexes using numeric attributes in the attribute table with ArcGIS? The data I have in my table are area and ...
1
vote
1answer
1k views

Python GDAL: degrees to meters without reprojecting

I am trying to get senseful results in my Python script. I want to measure distance between features in a shapefile. I'm working with the SRS: GCS_WGS_1984, so my units are in degrees. But for the ...
1
vote
0answers
410 views

Python Addin toolbar- Environment mask parameter not being recognised?

I've created a button on a python addin toolbar which uses the selected features from the selected layer in the TOC, creates a feature layer from that selection and uses that feature layer to set the ...
1
vote
1answer
290 views

How to set a spatial filter with Python/GDAL?

Is there a way with GDAL (Python) to set a spatial filter (bounding-box) on a raster before I process it? I want to read it as an array. BandReadAsArray(band, xoff=0, yoff=0, win_xsize=None, ...
2
votes
0answers
254 views

RT Sql Layer plugin giving an error [closed]

I am trying to use the aforementioned plugin with QGIS 1.7 and Postgres 9.0/PostGIS 1.5. Added a PostGIS spatial layer w/out a problem and then clicked on the RT Sql layer button which displayed the ...
1
vote
0answers
65 views

Script Tool Problems ArcMap 10.0

I Have a scipt tool that runs when input shape files are added from the table of contents (added from drop down menu.) However this tool will not run when they shape files are added using the add file ...
1
vote
1answer
216 views

How to iterate all input folders (containing coverages) using Python with ArcGIS 9.3?

I'm trying to write python scripts to batch convert thousands of coverages to shapefiles in arcgis 9.3. The coverages files are in different folders: d:/area_A/building d:/area_B/building ...
0
votes
0answers
217 views

Dynamically generating data for map tiles from Python function

I'm brand-new to GIS and relatively new to web services. I've found a ton of great resources on the web, but I'm having trouble addressing one specific issue: One of the data layers on my planned map ...
0
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0answers
88 views

Sextante script for statistic info

I want to generate a script for getting statistic information window from selected feature. For example i have two layer building(polygon) and railway(linestring). By using this tools i got a window ...
5
votes
2answers
426 views

How to create a point along a line given a distance from another point

I'm trying to figure out a point(D) on B-C that is a specific distance from A. I really don't have any idea on how to proceed with the ellipsoidal math so I figured I'd ask here. How would I figure ...
0
votes
4answers
428 views

Resolving Arcpy “GetObject not point” Error

I'm new to Python (v 2.6.5) and am trying to write an ArcMap (10) script that reads the vertex coordinates of a polygon shapefile which includes a small hole (doughnut polygon). I've been working ...
0
votes
1answer
595 views

How to create a report of all feature classes in a geodatabase?

I am not getting any response from this script and no error displayed at all I am writing this script to help me display the feature classes in my geodatabase Here is my script import arcpy ...
16
votes
1answer
5k views

How do I get the pixel value of a GDAL raster under an OGR point without NumPy?

I am working on a computational model of the abundance of wild pollinators across a landscape. The model itself is complete, and I am now struggling with a post-processing step. I have my GDAL ...
0
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0answers
95 views

Create Vertex and add empty attributes to it

How can I create a vertex(and then a point feature on the vertex) on a polyline and give it some empty attributes(create fields), move an existing vertex, delete vertex? I am in ArcGIS environment and ...