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

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OSR Python testSR.ImportFromEPSG(4326) returns empty spatial reference

This is empty using Python .ImportFromEPSG(4326): import osr #this fails: testSR = osr.SpatialReference() testSR.ImportFromEPSG(4326) print testSR.ExportToPrettyWkt() #why did the import from EPSG ...
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0answers
19 views

Creating a field calculator function that can cast string to a percentage value in a related field?

I am having issues trying to create a field calculator function based on a coded domain string parameter combined with a numeric field to obtain a percentage output. The example in question is as ...
0
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3answers
29 views

Cropping a Shapefile into a Rectangular Box with Python pyshp

Using 'pyshp' I am hoping to reduce the set of US highway shapefiles to only those in Puerto Rico. The idea is very easy since I only need those pieces which fit into the window. >> import ...
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0answers
35 views

Qgis 2.8, gdal python scripts gives error at end of process

I am using Qgis 2.8.1 64-bit (Standalone installer) which also packages a number or other applications, like OSGeo4W Shell, Saga GIS et.c. In the OSGeo4W Shell I am encountering a problem with some ...
1
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1answer
16 views

How to Convert db.ListProperty(GeoPt) to GeoJSON Polygon

My Python Google App Engine (no tag?) app has a datastore model of an Area of Interest, simplified as import geojson class AreaOfInterest(db.Model): name = db.StringProperty(required=True) ...
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1answer
66 views

Extract data from netcdf using a shapefile polygon in python

I need to subset data from a NetCDF using a specific shapefile. The data are sea surface temperature and ocean color at 1/4 degree resolution. I have 4 polygons describing the US. Northeast ...
0
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1answer
651 views

ArcPy SelectLayerByAttribute Error and how to control GP output layer name

I have a rather long script that first references an SDE feature class (non-versioned) to perform an attribute selection based on a SQL selection. I've been unable to figure out why the script will ...
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1answer
68 views

Unable to add attachment to ArcGIS Online feature service using Python and REST API

I am attempting to use Python to add attachments to an ArcGIS Online hosted feature service, but I'm getting an 'Unable to add attachment to the feature.' message when I run the following code: ...
3
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2answers
68 views

Accumulated value from many rasters python/arcgis10

I need to calculate an accumulated value of temperature (as an additional raster) from many rasters. Is there any option to do this in ArcGIS 10 or any hints for a python script?
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1answer
61 views

How to call QGIS modules (qgis.core) from python idle as I can call arcpy

I was trying to set up path to be able to call qgis modules as it defined in their website Introduction and set PYTHONPATH=c:\qgispath\python . I also try to follow suggestion in link below How to ...
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1answer
202 views

Python: TypeError: a float is required

I have a python script with some parameters - see screen. You see the last parameter is of type Double, default Value 0. The code i have this: Ausrichtung = float(arcpy.GetParameterAsText(9)) if ...
0
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1answer
58 views

How to delimit point distances in ArcGIS for Desktop per thiessen polgyon

I have 2 shapefiles. The first set contains xy pair for 1100 hospital locations. The second pair contains xy of villages about 7000 that are served by the hospitals. This means each hospital serves ...
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1answer
26 views

Using pyQGIS transform a layer of polygons into a layer of holes inside a bbox

I'm using python in QGIS. I have a layer of polygons (its a result of some earlier dissolving and has no overlapping polygons but some holes and islands in holes etc). I want to build a new layer ...
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2answers
380 views

Convert code VB to Python

I need to convert this code to be used by python in ArcGIS if [Field_1] < [Field_2] : pd = [Field_1] else: pd = [Field_2]
2
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1answer
21 views

Unable to compile using make test in Linux

While trying to compile my test plugin I encounter this error, for the moment I can't figure out why, last week I had some issues on windows but eventually solved them via OSGeo Shell but this time ...
0
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1answer
42 views

address standardizer code in python for street featureclass

In my system I have featureclass Street and having fields. Featureclass : Street Input fields: NAME;STREET_PREFIX;STREET_NAME;STREET_TYPE;STREET_SUFFIX output fields: ...
3
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1answer
67 views

How to remove a specific unique value with arcpy

using arcpy, i would like to remove,from 50 mxd files, a specific unique value called "residence a" (exist in 3 layers) from the table of content. so i will get this result: The value of ...
0
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0answers
17 views

Error 010240 when calculating mean of a list of rasters - Cell Statistics

I'm trying to calulate the mean value of a list of rasters but I am always getting the following error: RuntimeError: ERROR 010240: Could not save raster dataset to < value > with output format ...
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0answers
178 views

WindowsError: [Error 32] The process cannot access the file because it is being used by another process

I am reading images (through Python) and do something. These images are placed in a temporary file, through: tf = tempfile.mkdtemp(filename) I use gdal to read the images (short part of code): ... ...
0
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2answers
92 views

How to automate specific workflow best (QGIS 2.8)?

For a project of mine, I'd like to solve a spatial analysis using QGIS. Until now, I have never automated anything GIS-related except for some rather easy steps in ArcGIS using the model builder, so ...
3
votes
2answers
853 views

How to debug 'Layer is not valid error' from Python plugin?

I'm trying to understand what goes wrong with a QGIS python plugin. Basically I'm trying to render a series of POINT. The query works fine, at least giving it by hand from inside PostGIS DB: "SELECT ...
1
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1answer
42 views

QGIS crash when using args=0 with qgsfunction

I am trying to define a custom function in QGIS 2.8.1 that takes no arguments. from qgis.core import * from qgis.gui import * @qgsfunction(args=0, group='Custom') def test(value1, feature, parent): ...
2
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1answer
223 views

How to use SAGA ShapesToGrid via Processing in a Python plugin?

I run these lines in my code: vectorlayer_vector = ftools_utils.getVectorLayerByName(inputLayer) Elevation = self.lineAttrib.currentText() cellSize = int(self.linePix.value()) outPath = ...
13
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1answer
970 views

How can I utilize NumPy arrays to optimize big data geoprocessing?

I'm interested in learning how to utilize NumPy arrays to optimize geoprocessing. Much of my work involves "big data", where geoprocessing often takes days to accomplish certain tasks. Needless to ...
3
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1answer
532 views

Help with scripts for processing raster files with the raster calculator in QGIS

I am trying to process some raster files using python scripts in Qgis 2.20, and I have been having trouble finding any documentation on using raster calculator in scripts being run in the processing ...
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0answers
53 views

How to write features in file geodatabases (FileGDB) with GDAL and Python?

I am trying to copy features from a spatiallite database to a filegeodatabase. The target FileGDB already exists with the required feature classes. I am using the FileGDB-API 1.4 on Ubuntu and Python ...
0
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1answer
126 views

Arcpy MakeFeatureLayer won't loop

The arcpy snippet below is intended to generate a list of technicians scheduled to work, and then generates a unique feature layer for each one's stops. fcStops = "TaskRoute1016" with ...
0
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1answer
298 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
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1answer
142 views

Weighted Overlay - passing parameter as text error?

For some reason when hardcoding the save path for the wieghted raster just before runtime it works perfectly. Like such... arcpy.env.cellSize = "90" arcpy.env.workspace = r'G:\Xcel\Route ...
2
votes
1answer
97 views

Processing plugin Python error on startup of QGIS 2.8.1

I've been running QGIS with no issues for several versions now, but after I upgraded to 2.8.1 Wien I had trouble running two plugins: qgis2leaf (which I believe depends on Processing) and Processing. ...
3
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4answers
88 views

Python Script create spreadsheet with exception

In the following Python Script, I would like to create a spreadsheet (Excel would be fine) with the Exception results instead of just printing "There was an error--->..." to be able to keep track of ...
1
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1answer
132 views

Arcpy addin editable textbox on tool bar

I would like to add an editable toolbox on an arcpy addin toolbar. This would be used to change values of a threshold but I don't think this is currently available. (What I would really like is a ...
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0answers
60 views

open-source code for the map matching algorithm

For map matching of the GPS data to the network data, there is a algorithm from Schussler, N. & Axhausen, K. (2009a). Is this algorithm released under open-source license ? Where can I find this ...
4
votes
1answer
74 views

Dump a GeoJSON FeatureCollection from Spatialite query with Python

Given a Spatialite database, holding a table with a geometry column and some other attribute columns. I want to query that table in a Python script and get a GeoJSON FeatureCollection string in return ...
0
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0answers
23 views

How to publish a IDW GP service with python in ArcGIS 10.1?

I know someone has ask a question about how to publish a gp service with python.And the answer is using arcpy.CreateGPSDraft. But My geoprocessing tool is IDW, and I find the return value isn't a ...
2
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4answers
2k views

Possible to add multiple fields in single arcpy statement?

I'm trying to add multiple fields to a table using arcpy and am wondering if it's possible to have multiple fields declared in the AddField management, and their values, separated by commas or ...
0
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2answers
55 views

Python Crashes when Running ArcPy's ExportToPDF(), ExportToPNG(), ExportToJPEG()

I am attempting to loop through a folder of ~400 .mxd's and save each to a .pdf in another folder. All tested arcpy.mapping export functions (pdf, jpeg & png) kill python without a chance to ...
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0answers
27 views

Field calculator language [duplicate]

I am trying to edit an column of numbers in to texts. For example, if the SITE TYPE is 2 then the site_type (an added field which is blank) is Industrial. If there a way to use python to make it work? ...
1
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1answer
124 views

Loading Oracle Spatial Layers in standalone python qgis

I used below script to connect to postgres and load layers successfully.I want to aceive this using Oracle Spatial for both vector and raster loading.How can I achieve that?In other words what is the ...
0
votes
1answer
172 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 ...
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0answers
57 views

Compression Algorithms output files larger than the originals. Why?

I'm currently attempting to write a script that will compress a few hundred .tif files. I've tried two approaches, first I wrote a script in Python using CopyRaster_management() function and the ...
0
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0answers
25 views

batch save MXDs to group layer files using ArcPy

Does anyone have / know of a script that converts all the MXD`s in a folder to individual group layer files ? It needs to use the MXD name as the group layer file name.
3
votes
3answers
95 views

Using Python to count records and show difference

I'm trying to find an example of a python script for ArcGIS 10.1 that will get count of a FC in my SDE and get count of a FC in an incoming FGDB update and then write the difference to a log file. We ...
1
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3answers
46 views

Generate a string based on an integer range

After some initial research, I was unable to find a solution for the following issue. I'm sure there's an answer to this question already floating around here somewhere, but hopefully someone can give ...
0
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1answer
32 views

GDAL2Tiles crash

GDAL2Tiles seems to crash after generating tiles and no google viewers are generated, but only openlayers. This is the code I run: os.system("gdal_translate -of VRT -a_srs EPSG:4326" + ...
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1answer
4k views

Using the arcpy.UpdateCursor to delete rows doesn't delete based on counter?

I am trying to delete rows from a shapefile using arcpy.UpdateCursor. The first thing I did was get a unique list of values from the key field "PolyGUID", then I iterate that list doing a ...
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2answers
213 views

How to plot Storm Prediction Center (SPC) Shapefile using python

I am trying to make a plot of the SPC's thunderstorm outlook using Python. I have downloaded the shapefile from this website http://www.spc.noaa.gov/products/outlook/day1otlk.html. Then I use this ...
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1answer
307 views

Polygon Neighbors Analysis script (ArcPy 10.1) producing erroneous results?

I'm struggling with a python script that is supposed to calculate a field for a polygon feature class. The calculation is of the average of a field value (P_TOT_DEV) for each of a given polygon's ...
0
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0answers
20 views

GDAL Python and postgis raster?

I'd like to create a postgis raster using GDAL and python. I can get the driver easily: drv = gdal.GetDriverByName("PostGISRaster") But how can I create a new raster table? I can't find any ...
17
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3answers
807 views

Is it possible to look at the contents of Shapefile using Python without an ArcMap license?

I wondered if it is possible to look at the contents of a shapefile using Python without having and ArcMap license. The situation is that you can create shapefiles from many different applications, ...