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

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Find and replace unicode character in a shapefile

I've found several example of script and blog posts on working with unicode characters, but I haven't been able to make anything works so far... It's a little frustrating I have a shapefile encoded ...
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148 views

How to interact layers with a nested loop?

I've dealing with the code below with such a long time. I have to show in a raster image the result of calculating the cost of the electricity for a solar plant. The thing is that I have to interact a ...
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1answer
1k views

How to change vector attributes values?

I want to change vector attributes values. i could not get the command fet.setAttribute indeed, it is mentionned in http://hub.qgis.org/issues/7223 that: "The QgsFeature instance now must be ...
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976 views

Select Layer by Location - Arcpy - Why are my inputs being interpreted as invalid?

I am working on a tool in a python toolbox and am totally confused about what is going on and causing my select by location operation to fail (Error 000368). I am trying to select the features in one ...
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1answer
606 views

Using Python if/then/else to return value from either of two fields based on value of third using ArcGIS Field Calculator?

I'm trying to avoid manually inputting Begin and End engineering station values already inputted into a seperate field. I'm dealing with(4) fields: Begin_Sta End_Sta Beg_End and Station. The ...
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728 views

Can you use arcpy.Copy_management() with in_memory tables?

I have a table in an ArcSDE GDB I'd like to step through using Python. For performance reasons I wanted to load it into memory like so: arcpy.Copy_management('C:/GDB.sde/MyTable', ...
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583 views

Python scripting for ArcPad Checkin

I can use ArcGIS Desktop model builder to leverage the ArcPad Check In Tool. When I run the model it executes successfully. When I export the model as python I get this code: import arcpy # Local ...
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3answers
308 views

Why do I get a no module error when I try to batch process in Arc10?

I was trying to batch reproject a set of shapefiles and I kept getting the error No OS Module As the set was relatively small I just did it individually, however I want to be able to batch process in ...
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610 views

How to translate ESRI cursor example to pyQgis?

For example, how to translate this code into pyqgis? rows = gp.UpdateCursor("D:/St_Johns/data.mdb/roads") row = rows.Next() while row: row.buffer_distance = row.road_type * 100 ...
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2answers
847 views

arcpy.Delete_management not deleting

I'm struggling with deleting an mxd in a for loop. My code is: import arcpy, glob, os, datetime, time from time import strftime for filename3 in glob.glob(os.path.join(folderPath, ...
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308 views

GetCount_management From ArcGIS ToolValidator

We want to check if features are empty in the ToolValidator. When you call GetCount_managment() and background processing is on, there is a popup from our validation step. Is there a different ...
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2answers
3k views

Get extent of Georeferenced Rasters in Python and output to polygon shapefile

I would like to create a shape file containing the extents of each of the rasters in a directory. Is it possible to capture the extent of a raster using Python? I have tried ...
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4answers
1k views

Install other python distributions [e.g. Python(x,y)] on top of ArcGIS installation ?

I'm using ArcGIS 10 and would like to use various additional libraries that are not included in the delivered version of ArcGIS (esp. numpy and matplotlib). First I tried to install them manually as ...
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3answers
515 views

python: Replace Variable in VB-Expression-File (.cal) [ArcGis 9.3]

I'm trying to modify a VB-Expression saved in a cal-file: dim out if [D19830701]=-9999 then out= [D19830501] else out= [D19830701] end if __esri_field_calculator_splitter__ out with this ...
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2answers
30 views

GeoTiff to ndarray

What is the most elegant way to import a multiband GeoTiff as a ndarray using Python? The most common approach I've seen is as follows: from osgeo import gdal arys = [] ds = gdal.Open('sample.tif', ...
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1answer
33 views

Error using arcpy.da.SearchCursor and MakeFeatureLayer

im trying to write a script that allows me to iterate through my map layers, and for each layer, iterate over each feature and add a field that gives the location of the feature using my index layer ...
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2answers
51 views

Using raw_input python to accept string with a dash (-)

Hello I have the following python input. The user will enter a value with a dash always. E.g. 2015-0001 Var1 = raw_input("Enter the number with dash: ") ...
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2answers
105 views

Problems with plugin/installer manager in QGIS 2.6.1 Debian

An error has occured while executing Python code: Traceback (most recent call last): File "/usr/share/qgis/python/pyplugin_installer/installer_data.py", line 460, in xmlDownloaded if ...
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1answer
68 views

Creating Self Executing Python Script (*.py)?

Trying to figure out how to create self executing python scripts with using the ArcGIS python window. I'm ok (generally) when developing and running scripts inside the python ArcGIS windows but ...
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1answer
65 views

Update a field for similar values in the second field based on third field value

So I have the table like this: City Distance NearFeature Comments A 90.5 131025 A 0 781446 B 15.5 131057 B 42.2 140521 C 21.7 784116 C 0 ...
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4answers
113 views

Calculate Field with Python Issues (If statements)

I don't know a whole lot about python and scripting, so I was hoping somebody could give me a couple pointers on fixing some code. I am trying to calculate a "final results" attribute field. The ...
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1answer
70 views

Computing intersections for each geometry in a table

I have a table with many Linestrings and for each of these Linestrings I need to figure out which other Linestrings, from the same table, intersect with it. If I recall correctly this gives me a ...
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3answers
72 views

Determining Y coordinate for Create Fishnet from desired Angle of Rotation in Python/ArcPy?

On the ESRI website it says: How_Create_Fishnet_works Calculating a value for the y-axis coordinate If you know the angle of rotation, you can compute a value for the Y-Axis Coordinate parameter as ...
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2answers
31 views

QGIS 2.4 crashes when symbolizing QgsComposerShape in Python with ScriptRunner

I'm attempting to use ScriptRunner to output a jpeg of a red rectangle using QGIS Composer to understand the QgsComposerShape. Everything works except QGIS crashes when the symbol is applied. The ...
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1answer
83 views

How to work with accentuated strings in Python scripts in ArcGIS Desktop Field Calculator?

` pre-logic: def myCalc(name,nameVal): if (name == nameVal): return 1 else: return 0 var_name= myCalc(!Epulettipus!,"Lakóépület") ` This doesn't work with accentuated strings. (But ...
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65 views

building dictionary from feature class field values, how can I ensure there are no duplicate values per key

I found this code sample that builds a dictionary from two fields; the end result is a concatenation of all values per key to a new field. It's a great tool except that it doesn't account for ...
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1answer
46 views

How to ascertain if a cell/field contains a value in ArcGIS attribute table

I have done a bit of research on this but can't seem to find an answer. I am wondering if there is a way to identify whether a cell/field in the ArcGIS attribute table contains a value using the ...
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2answers
110 views

How to concatenate double with string in field calculator with Python expression?

I'd like to concatenate my lat/lng with a few string fields in ArcGIS. What is the correct expression to use, avoiding VBA. I don't want to convert the lat/lng fields to string either. my 4 fields ...
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1answer
91 views

How to delete features/records in ArcGIS Server using Python

How can I use python to delete records from a table, or features from a featureclass, when they are stored in ArcGIS Server? using REST "delete features" in arcgis api for javascript shows ...
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1answer
132 views

What's the reason for this Invalid Layer “Cannot open GDAL dataset …” error

When adding a rasterfile with QGIS python console there appears an error when the first letter of a rasterfile to be added is not written in capital letters. Why this behaviour? Example case1: ...
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2answers
55 views

Creating shapefile from selection - remove from map

I am iterating over a shapefile and creating a new shape from each row. I will be creating several thousand individual shapes and do not want to inundate my TOC with that many layers (I bet ArcMap ...
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323 views

Installing pandas with Esri's python?

Trying to get pandas to import, but I'm getting what looks like an error caused by a failed dependency of the version of my Esri-provided numpy's compile, based on this stackoverflow posting. Here's ...
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1answer
159 views

User defined parameter within code block of field calculator - Modelbuilder - ArcGIS - Python

I am using Reclass within a Code Block in Field Calculator in a Model to calculate field values for a variable based on several other fields. Using reclass is much quicker than select and then using ...
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2answers
93 views

Raster' object is not iterable

I'm trying to calculate the percentage of cell counts in new raster and the new raster is created from an old raster based on the Value > 14. In my code, 1st for loop is for original raster and ...
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1answer
44 views

sum of raster counts

I'm trying to get the sum of "counts" in a raster. I have the code below which can successfully read the counts of each row in raster attribute and stores the counts in a list provided below. ...
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5answers
172 views

Calculations in if statement

I want to perform a simple calculation with the Field Calculator using this piece of script (note that all the elif statements are attempts for another syntax and non of the worked): def ...
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2answers
66 views

If-Then-Else statement in ModelBuilder has improper syntax

I have a model that converts a road network into a different schema for a different program. In one step of the model I am converting values for a field "Class". I wrote an If-Then-Else statement in ...
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2answers
58 views

Problems searching for attributes

I've come across this problem a few times and have not been able to find a satisfactory answer. I am new to python though so perhaps I have not been looking in the right places! Anyway, In ArcGIS I ...
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1answer
263 views

Script to “extract by mask” a list of raster files

I'm trying to mask a group of raster files and save the new rasters in a different folder using the same name of the original files. It doesn't sound as a difficult task, but I'm having trouble ...
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228 views

How can I group Points to make polygon via Python

I have an array of coordinates Point= [lat,long] ListPoint= [[38.203655,-76.113281],[38.10,-76.12],..] I wanna make a polygon that contains all these points ? There is a project developed by ...
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1answer
75 views

Arcpy Script tool

I'm creating a script tool and using the SelectLayerBy Attribute function (below), arcpy.SelectLayerByAttribute_management("cities_lyr", "NEW_SELECTION", '"CRIME_INDX" <= 0.02') However, I keep ...
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1answer
282 views

QGIS Map tools and Map canvas--QString errors

I'm trying to learn more about using QGIS Map Canvas widgets and creating custom map tools, so the information from the PyQGIS cookbook is very helpful. After trying to experiment with mywnd.py from ...
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1answer
183 views

Equivalent function to shapely's envelope in ogr?

I wrote a very simple python function that gives me the envelope/bounding box/...based on two coordinate pairs (ower left and upper right corner): # ... def get_bounding_box(self, ll_corner, ...
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1answer
102 views

Is it a good idea to use GRASS Algorithms for Geoprocessing in a Server Environment?

I´m designing a web-service to run in a server environment that will do some geoprocessing actions to datasets uploaded by users and send the results back. I´m programming in Python, and so far I´ve ...
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2answers
65 views

Fill Sinks of multiple rasters in a Python expression

I have 31 rasters that represent different watersheds and I would like to use the Fill (Spatial Analysis) tool to fill the sinks of all rasters at once in Python. All the rasters have the same name ...
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1answer
188 views

ListRasters not recognizing raster files in python

I have 2 rasters in my workspace, one in TIFF Format and the other in GRID format: "C:\ExampleFolder" When I use the python script: import arcpy >>> ...
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2answers
305 views

Efficient way to store multiple values of an x,y location in Python?

I am trying to read values from a stack of images and store them in a structure that will allow for easy readability. My current idea is to create a loop for x in width: for y in length: ...
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208 views

How to remove all selection from all registered layers using QGIS plugin?

I want to remove all selection from registered layer in QGIS using Python. I tried to clear the map canvas using: self.iface.mapCanvas().clear() self.iface.mapCanvas().refresh() but the ...
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947 views

How to terminate Python scripts in Processing framework properly?

I'm writing a Python script to use it in Processing framework. I need to cancel script execution if certain conditions are met (to save user's time). I tried to use sys.exit(arguments) command. The ...
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465 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, ...