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

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4
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2answers
692 views

Enabling time aware layers using arcpy

Is it possible to enable time aware on a layer programmatically? I can add a time-enabled layer to a non-time aware data frame as shown here: ...
15
votes
3answers
12k views

Listing all feature classes in File Geodatabase, including within feature datasets?

From python how can I build a list of all feature classes in a file geodatabase (*.gdb), including inside feature datasets? The standard example only lists feature classes at the top level of the ...
0
votes
1answer
336 views

Eliminating a column from a copied feature class via a fieldmap object in ArcGIS Python

The use case is exporting a feature class via a Python script (arcgisscripting v9.3x. Only a few of the columns are needed in the result feature class. I commonly use the fieldmappings/fieldmap ...
3
votes
2answers
4k views

How to export selected records to a .txt file

I am working on a project where I need to create a tool/method to export the attributes of selected features to a .txt file. I have point features containing addressing information, and the tool ...
4
votes
1answer
511 views

How to deal with direction (CW, CCW) of circles, in particular with shapely?

I am translating an input that describes zones by mixing segments and arcs. Arcs are given by a center, 2 points (beginning/end of arc) and a direction (CW or CCW). In a first prototypes using GDAL, I ...
12
votes
4answers
6k views

Clustering Trajectories (GPS data of (x,y) points) and Mining the data

I've got 2 questions on analyzing a GPS dataset. 1) Extracting trajectories I have a huge database of recorded GPS coordinates of the form (latitude, longitude, date-time). According to date-time ...
1
vote
2answers
556 views

How to create GRASS scripts in C# in Windows

Most of the tutorials that I have seen are under Python and Linux. Is it Possible to create GRASS scripts in C# or atleast in Windows. I can create scripts using a different language as a compromise ...
8
votes
5answers
2k views

Who uses FME Python extension and how?

I saw a great interface to FME with Python What you guys are doing with it? I want ideas.
0
votes
0answers
547 views

Change from data --> layout view using arcpy? (ArcMap 10)

The opposite, from layout to data, was asked and answered, but I can't figure out how to switch to the layout view from data view using arcpy. Can it be done? Thanks.
7
votes
3answers
3k views

How to create a circle in arcpy

Suppose I have a dataset where each record has an x,y and r (the centroid and radius of a circle). How can I create a polygon feature class containing parametric circles? Sorry to those who have a ...
4
votes
2answers
908 views

Calculate spacing of polylines along transects in ArcGIS

I have a shapefile with a number of roughly parallel lines in it, and I want to calculate the spacing between these lines using a number of transects across the map. How should I go about this? I ...
8
votes
2answers
6k views

How does one access a featurelayer in SDE via Python?

I am trying to use Arcpy to run the CopyFeatures_management script so that I can copy a featurelayer in SDE. What do I use for the input (and output, for that matter, since I'll be copying the layer ...
4
votes
3answers
2k views

How to format dynamic text element in Data Driven Pages [closed]

Is there a way to format the Name element generated as dynamic text from Data Driven Pages. This element serves as my title and it is too long and needs to be wrapped onto another line.
4
votes
1answer
132 views

Is it possible to install 9.3 Desktop Administrator as a standalone program?

I have ArcServer 9.3 installed on a server that I use for running scheduled Python geoprocessing scripts. I have several running, and now I'm trying to schedule one to rec/post, delete and recreate ...
3
votes
4answers
975 views

Append to text file using ArcGIS and Python

I have wrote a small routine using Python for ArcGIS (9.3) that will get the count of 2 data layers, calc a percentage, and then write the text back to a text file (CSV) to create a sort of "report" ...
9
votes
4answers
7k views

using shapely: translating between Polygons and MultiPolygons

[EDIT: the solution to this was simply to use OGR to read shapefiles. See geographika's example.] In an ESRI shapefile, there is no distinction between Polygons and MultiPolygons. Furthermore, there ...
2
votes
1answer
517 views

How do I group layers in Mapnik?

I might be thinking about this all wrong, but right now I'm using Mapnik's OGC Server, and using that WMS with OpenLayers. How would I group multiple layers (say country, water, state borders) into ...
10
votes
2answers
4k views

Point (of a linestring) within Polygon using ogr and Python

I'm currently working on a project in which I need to build a topological network out of the geometry features I find in shapefiles. So far using Ben Reilly's open source project I've managed to ...
4
votes
4answers
6k views

Merge overlapping lines in ArcGIS

I have a polyline shapefile containing a number of lines, some of which overlap. By overlap, I mean that they follow exactly the same path for some of their route, but also have bits that are not ...
16
votes
2answers
6k views

How to divide a polygon into specific sizes using ArcGIS?

I have several thousand irregularly shaped polygons in a shapefile. I want to be able to split each polygon into three areas, and to specify what the size of those areas (they sum to the previous ...
9
votes
2answers
781 views

Scriptable alternative to ArcScan (particularly vectorising lines within tolerances)

Sadly the answer to this question suggests that it is not possible to script ArcScan from within a python script. Therefore, does anyone know of any alternatives to ArcScan (either within ArcGIS, or ...
2
votes
1answer
349 views

ArcObjects ITextSymbol.GetTextSize in Python revisited: usage with StartDrawing and FinishDrawing methods

I am using ArcGIS 10.0/ArcObjects and Python 2.6. I am trying to get the usage of the ITextSymbol.GetTextSize method correct. The syntax, as established in an earlier question, is: dblx, dbly = ...
4
votes
3answers
2k views

Why would “import arcpy” hang Python script run from DOS/cmd prompt?

I have a very small test script (test.py) that I use to see if Python is installed and ready to use ArcPy. All it contains is: print "Starting" import os print "OS imported" import arcpy print "ArcPy ...
3
votes
1answer
373 views

Can you access ArcScan from a python script?

I'm using a python script with ArcPy in ArcGIS 10, and want to access some ArcScan functions. Is this possible? I can't see anything in the documentation about it, but I can't really find any very ...
4
votes
2answers
2k views

Programmatically alter AliasName for fields defined in layer file (not underlying source)

Is there a way to alter the AliasName on a layer file only, and not the underlying shapefile or feature class? I have a few hundred layers that define joins between hundreds of tables with census data ...
6
votes
2answers
4k views

How should I use GDAL to perform a transformation?

Greetings, I am a student who wishes to use GDAL to transform a series of images from Lambert Conformal Conic (EPSG: 9802) to Google Earth's WGS 84 (EPSG: 4326) for a web mapping project. I know ...
6
votes
3answers
2k views

ArcMap/ArcObjects - Drawing graphics onscreen: Explanation or tutorial for Draw/Refresh/PartialRefresh methods?

I find myself woefully lacking in understanding of when, why, and how (which type) to do screen draw/refresh/partial refresh. For instance, in a standalone Python script outside the application ...
5
votes
3answers
2k views

Python, comtypes and ArcObjects: Error creating AppROT object

I am experimenting with comtypes and ArcObjects under Python 2.6.5 and ArcGIS 10 SP1. I'm using the pure Python method to wrap the ArcObjects OLBs described in this answer, but getting an error in the ...
4
votes
1answer
218 views

ArcObjects ITextSymbol.GetTextSize in Python: Why are the out params equal to 0?

This is related to the question I asked earlier about the syntax for this method under Python and comtypes. Now that I know the syntax and am trying to use it, the returned out params are equal to 0. ...
6
votes
3answers
4k views

Using model builder, how can I extract certain fields for 1 selected feature from a point shapefile file with multiple features?

I have a point shapefile that is filled with many features. If I have 1 feature selected I need to be able to export certain fields of that selected feature (ID, lat, long) into a dbf file. What ...
3
votes
1answer
832 views

ArcObjects: How to get from IFeatureClass on annotation feature class to IAnnoClass?

I am working in Python 2.6 and ArcGIS 10.0 through comtypes, so I have full ArcObjects access. (See the answer I tacked onto the related question "How do I access arcobjects from python?") That ...
3
votes
1answer
257 views

ArcObjects ITextSymbol.GetTextSize in Python: How do I define two input variables that get populated by the method?

I am using Python 2.6 and ArcObjects in ArcGIS 10.0 to build and draw, among other things, graphic text on the current display. At one point I need to use the ITextSymbol.GetTextSize method. In a ...
20
votes
6answers
16k views

Defining projections for multiple shapefiles in ArcMap?

I have over 100 shape files that don't have .prj file and thus when I bring them into ArcMap 10 they show the coordinate system as unknown. I know all of the shape files coordinate system is GCS WGS ...
3
votes
1answer
1k views

calculate value using maximum value from different feature class

I'm trying to get the maximum numeric value from one feature class and use that value in an expression to calculate values of a different feature class. fc2.bldg_id = max(fc1.bldg_id)+1 Can this ...
0
votes
4answers
9k views

Python Question - how do I extract a part of a string

I'm building a tool in python and for that I have a question: I have a string such as "Denver.dwg Group Layer\Denver.dwg Annotation". How do I assign to a variable (for later print) only the first ...
5
votes
1answer
2k views

Updating a point's geometry based on geometry of another feature class

I'm looking to update the point geometry of lets say "oldFC" by obtaining the shape geometry of "newFC" and applying that to the "oldFC". I also want it to grab the value in the ID field in ...
8
votes
4answers
2k views

Best way to find the polygons crossed by a line

I'm trying to find all the polygons crossed by a single line (a GPS track). I'm using the OGR library (from python) for computing this, but it's currently a bit 'brute-force' (and slow). For every ...
8
votes
5answers
6k views

update one shapefile attribute table with values from another dbf table

I try to explain here what I am trying to do: I have one shapefile and one independent dbf table with the same fields. In the dbf table all the fields are populated but in the shapefile attribute ...
7
votes
1answer
1k views

automated georeferencing

I am attempting to fully automate the process of georeferencing a load of .png files - i have xml file containing the co-ordinates - but how can i use them? Does anyone have any advice?
7
votes
2answers
1k views

selecting by attribute and specific value replace

I want to select all of the features by attribute where the attribue in myattrib is like... Selection "criteria H". That is not a problem. However then I need to replace (myattrib," H", "") except ...
6
votes
4answers
1k views

Raster to Polygon Scripting Problems

I am trying to make a script which selects every .png file in a folder beginning with the letters "LG". I then want the scipt create a shapefile, replacing the "LG" with "SH", and then i want the ...
8
votes
1answer
4k views

Problem with setValue() function in ArcGIS 10

I'm trying to add data to an attribute table in ArcGIS 10 using the following code: def make_floor_no( shapefile ): "Makes header for number of Floors (FLO) and calculates value" fieldName = ...
6
votes
1answer
267 views

Does Arcpy work for Engine or Server the same as Desktop?

I am contemplating a project where there is not going to be access to ArcGIS Desktop and wondering if Engine and/or Server install ArcPy and Python? Is this possible? Does anyone have an example?
4
votes
2answers
325 views

Unique Character Generator Help

I am working on a script that will populate 3 letters into a field. I have to use letters due to field limitations and to make sure that I have enough combinations. I'm not really sure where I am ...
3
votes
1answer
1k views

How to change the datasource with python?

How do I change the datasource of all layers in a map document using arcpy and python
11
votes
4answers
2k views

Looking for a pythonic way to calculate the length of a WKT linestring

I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
9
votes
1answer
7k views

How to create a script tool that will create a copy of a feature class and offset it by a given distance? (arcpy)

I want to duplicate a polygon feature class and offset all of the polygons by about 10 feet in both the x and y directions. I asked if there was any way to do this last week, and I was informed that I ...
9
votes
4answers
2k views

how can i convert a shapefile to lat and lon boundaries?

i have a shapefile of country subdivisions and i would like to extract an array of bounding lat and lon for each division.. is it possible to do?
19
votes
6answers
582 views

Python for GIS on a thumb-drive

I'm looking at putting together a light Python install on a thumb drive that I can take to client offices and do some basic GIS processing. I'm thinking of installing the following: PyScripter ...
3
votes
2answers
281 views

Segmentation Fault (segfault) when using OGR CreateField() in Python

Receiving a segfault when running this very short script in Ubuntu. from osgeo import ogr, osr shpfile = 'Census_County_TIGER00_IN.shp' def cust_field(field): '''cust_field(shpfile, field) ...