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

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1answer
322 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: ...
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0answers
23 views

Determining Centroidal Longest Flow Path using Python (and not HEC-GeoHMS)?

I've been using the Centroidal Longest Flowpath from the HEC-GeoHMS Basin Characteristics Toolbox. The explanation from the HEC-GeoHMS manual is that the centroidal longest flowpath is computed by ...
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1answer
150 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 ...
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3answers
77 views

Autopopulating text field with string and number combination

I have an attribute table with a text field which indicates a unique identifier for each row. The identifier includes a combination of text and numbers, sequentially increasing, as follows: ...
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2answers
280 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
28 views

XML Document points to the wrong location after using arcpy.BatchProject()

I'm trying to reproject a number of shapefiles representing contours from NAD_83_Albers to NAD_83_UTM_Zone_9N using arcpy.BatchProject(), but I have to use python/regex to preserve a particular file ...
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2answers
54 views

Capitalizing 5th word in Python string? [closed]

I understand how to capitalize first word using !CITY_NAME!.capitalize(). However, if I have a string in a record and I want to capitalize the fifth word, what is the code for that? Ex: 3 Boundary ...
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8answers
11k views

How to Remove return/newline (\n) character from Field using Python and Field Calculator?

I have a geodatabase table with a field that I'm trying to remove return characters (new line). I found this post (How can I remove (chomp) a newline in Python?) of how to do it, however it is not ...
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2answers
46 views

Reserved Ampersand Character in Label Expression of ArcGIS for Desktop?

I have this code which works... def FindLabel ([NUMBERNAME], [NUMBER], [BLOCK], [SURNUM]): lineone = "A:"+ [NUMBER] absName = "<CLR red='255'><FNT size = '14'>" + [NUMBERNAME] ...
2
votes
1answer
203 views

Accessing CRS info with pyqgis in a standalone application

I'm currently having trouble accessing and defining CRS information in a standalone application. I've read the API documentation and have tried it in the python console in QGIS 2.2.0. The python ...
6
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1answer
160 views

How to access file geodatabase (.gdb) rasters with GDAL?

I'm working on a tool that converts raster layers to arrays for processing with NumPy, and ideally I would like to be able to work with rasters that come packaged in a .gdb without exporting them all ...
2
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1answer
52 views

Execute ogr2ogr from python

I tried to execute ogr2ogr from python with this shell command: ogr2ogr.exe --config PG_LIST_ALL_TABLES YES -f "PostgreSQL" -append PG:"host=hostnamet user=username password=password dbname=dbname" ...
2
votes
2answers
154 views

Add OpenLayers layer from QGIS's Python console?

On QGIS 2.4.0-Chugiak the Openlayers plugin is found under Web menu rather than the Plugins menu. How can you use the Python console to add a Openlayers Google Maps layer? The following code give us ...
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0answers
36 views

ArcGIS calculate average value

I would like to get the average value of specific attributes. I have a table with columns like: ID, P1, E1, Age1, P2, E2, Age2, P3, E3, AverageAgeP, AverageAgeE Sometimes there is a value for P, ...
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1answer
29 views

Using label expression to label highway with last group of numbers in field

I'm using Tiger road files and I want to label the highways with their shield number. Tiger has an inconsistent naming convention for road features; I am specifically concerned with the highways. I ...
3
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1answer
19 views

Problems with Reclassify and RemapRange in ArcPy?

I'm having a bit of trouble with a script that uses ArcPy. I keep getting the following error: ExecuteError: ERROR 000622: Failed to execute (Reclassify). Parameters are not valid. ERROR 000628: ...
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2answers
54 views

32-days composite using LST 8-days Data

I want to make a 32-days composite from 8-days LST data by taking its average value, but I am facing a problem in checking QC-day, the other thing is, due to data gaps (missing DN values) we cannot ...
1
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1answer
35 views

How to convert/export a large number of attribute's information shapefiles to txt/csv format using a python script

I'm using the 2.8.1 Wien QGIS version. I have a large number (more than 5000) of shapefiles that I want to convert to a csv or txt files to extract, to tables, the atributte information. The ...
0
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1answer
304 views

Get shape file polygon attribute value at a specific point using Python (e.g. via PyShp)

I have a shape file comprising multiple polygons. These polygons have attributes. I am trying to write a script in Python that takes a co-ordinate point, determines in which polygon it falls, and ...
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0answers
18 views

NetCDF4 Files: Missing Projection & Varying Dimensions (Multiple Files)

All, I hope you can shed some light on issues I've been having regarding NCEP Reanalysis-I netCDF-4 file format: First issue, Projection information is not stored on the downloads I obtained from ...
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0answers
32 views

way in R or Python to add image/video in map plot marker click popup/infowindow

I have many different (lat,long data) points of world associated with unique place names and corresponding each point specific image or video data. Now I want to create an html file where if user ...
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2answers
203 views

What's the most efficient way to load feature attributes into a numpy array?

I am currently working on an add-on that relies on the user choosing fields of tables (that can be from shapefiles, csv or dbf) that are open in QGIS and then making computations with such data. ...
3
votes
1answer
890 views

Calculate attributes to table based on other attributes

I am going through thousands and thousands of road lines and giving them a value based on QC with imagery. So for instance for the add_data field I give it one of these five numbers: 0 = not ...
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2answers
579 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
2
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1answer
64 views

QGIS Plugins & Tools that replicate Select ArcPy Tools

I developed a complex python application for road generation from GPS Devices that uses a few Arcpy Tools. I want to try and replicate this Applications functionality using a freeware like PyQGIS ...
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2answers
58 views

QgisInterface.addVectorLayer Error

I am Esri-trained, trying to move into QGIS using Python. Simply trying to add a vector layer in Qgis returns the below error: TypeError: QgisInterface.addVectorLayer(QString, QString, QString): ...
3
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1answer
312 views

Putting coded domains into list to be created in Python script?

I have a large list of coded domains. They are numbers like: 01.6530.01, 05.7991.08, 05.7991.01, 05.7991.06 The code will be the exact same as the description. I've tried to make a list using: ...
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1answer
422 views

GDAL - How to get geometry type of a MapInfo TAB file?

I am using the OGR MapInfo File driver to read a MapInfo TAB file. However, the function GetGeomType() returns 0 which means 'wkbUnknown` even if the features in the TAB are only multi-polygons. Is ...
0
votes
1answer
47 views

Using If Statements in ArcGIS Calculate Field?

I've never used Python scripting before and can't seem to figure out how to use an If statement in the Field Calculator tool. I have a field called 'MAX_GRIDCODE' which returns the highest force a ...
3
votes
2answers
1k views

Moving cursor backward i.e. opposite of row = rows.next()?

Can anyone tell me if there is a way to go up one row in python cursor? i.e. opposite of row = rows.next()
3
votes
1answer
257 views

How to clip a Oracle query layer directly in a Python script?

I have a query layer directly running from ORACLE database in a MXD. I want to clip this layer with a layer being created in another MXD in a Python based tool. My question is to do this clip ...
1
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1answer
205 views

Running GRASS functions in QGIS 2.4 from python console

I am using qgis 2.4 and i am looking for the "easiest" way to execute e.g. the r.in.gdal function from the python console in qgis. Specifically for r.in.gdal, I could not found this function in ...
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0answers
15 views

Skipping the string serialization in json.loads(OGRGeometry::ExportToJson())

I have a for loop that exports a bunch of OGRGeometry objects to a python array in what will eventually become a GeoJSON feature collection. Something like this: features = [] for feature in ...
2
votes
1answer
56 views

different way to build qgis python standalone application

There seems to be 2 different ways to start a Python QGIS standalone script. The official tutorial is using : from qgis.core import * # supply path to where is your qgis installed ...
3
votes
2answers
370 views

Can I Dynamically Update Symbol Ranges?

Background: I'm currently trying to dynamically change the ranges for a layer with new style graduated symbology. Problem: I thought it may be as simple as updating the ranges for the existing ...
0
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1answer
58 views

Create a Loop for Arcpy

I am looking for help to write a loop a arcpy.CalculateField_maagement process where the User is asked with the 'raw_input', prior to the tool running "Do you need to change a field value(yes/no):", ...
2
votes
1answer
201 views

Import error when utilizing QGIS's Python Init function

Based on the answer to Referencing Qt UIs external to plugin with python. I'm trying to utilize the "Layer Properties / Fields / Python Init function" to execute a file (test_file.py) that is located ...
1
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1answer
34 views

How to restrict panning in QGIS to a given extent

I'm going to build a QGIS standalone application. According to the requirements full extent equals to the extent of a predefined rectangle (say bounding box of a parcel). The application should start ...
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0answers
31 views

GRASS 7 (python:14221): Gtk-CRITICA Linux Mint

I installed GRASS 7 and QGis from the https://launchpad.net/~ubuntugis/+archive/ubuntu/ubuntugis-unstable (Trusty 14.04) in Linux Mint 17.1 two weeks ago (sudo apt-get install postgis libgdal1h ...
0
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1answer
38 views

How to extract information from world file of images into a DBF catalog file through PYTHON?

Here are thousands of pictures in JPG or TIF format with world file such as jgw and tfw. Inside each file, projection information for each pictures were contained. One example of the content for a ...
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0answers
53 views

import qgis.core problem with QgsFeature and QgsGeometry ImportError: DLL load failed: The specified procedure could not be found

I've tried several previous answers to similar questions - no luck. I've tried everything, nothing seems to work. This is the error I'm getting Traceback (most recent call last): File ...
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2answers
174 views

SnapToCurrentLayer in QGis2.8 with python programming

I have a polygon vector layer and I want to snap the vertex. def canvasMoveEvent(self,event):   x = event.pos().x()   y = event.pos().y()   startingPoint = QPoint(x,y) ...
2
votes
2answers
186 views

Debugging ArcPy ImportToolBox AttributeError: Object: Tool or environment <ConcatenateRowValues_AA> not found?

I am trying to use the ConcatenateRowValues tool provided by ESRI. My overall code for my script is working fine except when it tries to use the ConcantenateRowValues Tool. I start by importing the ...
2
votes
1answer
170 views

Python Error while installing Cartogram

I am quite new to GIS and qGIS especially. I would like to install cfarmers cartogram plugin. From what I understand, this has to be done manually - so I 've followed the instructions from ...
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1answer
79 views

Changing colours in GeoPandas?

I have a very simple map (http://www.nyc.gov/html/dcp/download/bytes/nybb_15b.zip) and I have never before worked with shapefiles in any way. Can someone tell me what I need to do in order to change ...
4
votes
1answer
454 views

Configuring spatialite database access for Python 2.6.6

I'm working on a GIS project, and I would like to implement and test some geo-spatial algorithms in Python. For this purpose, I will not only need sqlite, but also spatialite, in order to store and ...
0
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1answer
329 views

Spatial ETL Tools won't run “AttributeError: 'module' object has no attribute, etc.”

I have a python script that runs 5 Spatial ETL tools that I wish to run as a scheduled task. Each of the tools will run successfully from ArcCatalog and also from the ArcCatalog Command line. If I ...
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0answers
39 views

How to write a QGIS-plugin to be used in IntraMaps Roam 2.4.0?

I know some python, but I have never written a plugin for QGIS nor Roam before. I like to be able to turn layers on/off in Roam I have read the Roam's wiki, and I have managed to make a plugin called ...
3
votes
2answers
87 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?
5
votes
2answers
732 views

Load and display a layer from SQL Server using PyQGIS

I'm having a go at using pyqgis from within the QGIS python console to load a layer from SQL Server and display it. I feel like I'm part way there but I'm having a real issue getting the layer to ...