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

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2answers
408 views

Specify a GDB feature class using Python Tkinter dialogue box

I tried to specify a feature class from a GDB dataset through Python Tkinter tkFileDialog.askopenfilename. Below is the script. It worked for me in the past when I was dealing with .txt or .las files. ...
2
votes
1answer
65 views

How to find length of a discontinued line feature

I wanted to find the length of features in a road layer. So I go through each feature in the layer and used, line = feature.geometry().asPolyline() to find the points which particular feature is ...
2
votes
4answers
669 views

Converting a large set of GRIB2 files to a spreadsheet format

I have a large set of .pgrbf.grb2 files downloaded from the Climate Prediction Center, and I need to run statistical analyses comparing them to data that was produced locally in .csv format. I'm not ...
2
votes
2answers
98 views

ArcGIS Field Calculator passes European-formatted floats as tuples

I have the problem that the ArcGIS Field Calculator doesn't read a float number when it is included in Python by referring to the field that contains it, in this way: def giveResult(floatValue): if ...
2
votes
1answer
452 views

select random rows with python in arcgis

I am new to using Python in ArcGIS, and I wonder: how do I select random lines (or every two lines) of an attribute table? I must select these lines and calculate them, so they are different from ...
2
votes
1answer
756 views

How to properly import QImage from PyQt4.QtGui?

I am starting with QGIS python console. Naturally, I came across the PyQGIS Developer Cookbook. While trying to cut my way through it, I encountered a lot of problems with "undefined attributes and ...
2
votes
1answer
616 views

Python loop with address locator

I was given a list of addresses without any zip codes, and I'm trying to write a python snippet that will loop through a set of possible zip codes and make a set of geocoded shapefiles that I will ...
2
votes
1answer
288 views

Python and gdalwarp: change resolution of raster

I am new to GDAL and have been having some hard time figuring out how to change a raster's resolution and how to align it to another existing raster. I have come to the point where I have a raster ...
2
votes
1answer
429 views

Cannot load postgis layer from sql string in pyqgis

I'm trying to load a layer using the following code in qgis python console: sql = "(select the_geom, ID from mytable)" uri = QgsDataSourceURI() ...
2
votes
2answers
646 views

How we can get output for os.system() in python?

I wrote the following command in Geoserver rest-api using curl: cmd=curl -v -u admin:geoserver -XGET -H "Accept: text/xml" ...
2
votes
1answer
110 views

How do I rename rasters in an mxd by using my csv?

I have the following data in a csv: RasterName First name Raster 1 Aaron Raster 1 Paul Raster 2 Bryan Raster 3 Cranston Raster 3 Vince I have added these ...
2
votes
1answer
596 views

Pyproj: converting WGS84 to Robinson

I have a WGS84 coordinate pair (37.7749295, -122.4194155). I have an image that is a Robinson Map Projection of the world. I'm trying to write a python script to locate my WGS84 coordinate on my ...
2
votes
1answer
151 views

Problem with Python codeblock recognizing a field

'<'First Post Alert> I've been through multiple iterations / gyrations, and while there may be multiple problems here (and I'll appreciate feedback on all of them), the recurring issue is that the ...
2
votes
1answer
1k views

Is there any way to fast read pixel value using gdal in C#

I create with C# a series of lat/lon value pair in the code(using i, j loop) and I want to extract the pixel value based on either lat/lon pair or pixel location (i, j). I know there is one gdal ...
2
votes
1answer
983 views

Python support with QGIS 2.4 on Ubuntu 14.04

I recently updated my Ubuntu system to version 14.04. I added the sources and installed QGIS as per the directions on the QGIS website. Everything looks good, except for I do not have all the ...
2
votes
1answer
440 views

Definition Query then Zoom to Layer Automation?

I'm trying to create something in here. I want to have an automated process of doing a DEFINITION QUERY then ZOOM TO LAYER with one step. the concept is like that, a dialog comes up with one form ...
2
votes
1answer
374 views

How to use the MMQGIS plugin through the Python console?

I know how to make Hub Lines using the GUI, I want to know how to do the same using the Python Console, a tutorial would be great. Thank you
2
votes
2answers
437 views

How to switch to edit mode vector layers, in pyqt application based on qgis?

I do QGIS based application, I need to implement the ability to modify the geometry of vector layers in manual mode (editing nodes), how to do it?
2
votes
1answer
76 views

Zoom option error on gdal_tiler.py

I'm using the tiler-tools library from: https://code.google.com/p/tilers-tools/wiki/QuickStart And specifically this command: ./gdal_tiler.py --zoom=9-15 my_map.vrt To generate tiles. When I use ...
2
votes
2answers
344 views

How to calculate monthly maximum values from daily data in a 365 band grd?

I have a MINT2005.grd file which has 365 bands representing days of year from 2005. Each band is a 32x35 matrix representing the temperature at different latitude and longitude pair. How do I ...
2
votes
1answer
425 views

QGIS Python Scripting - Syntax definition

After playing around with the Model Builder and looking at the python scripts of what I make, I noticed some syntax which I can't find the definition anywhere. Here is a snippet of the python script ...
2
votes
2answers
203 views

Issues Reading a table from Geodatabase

I have scripted a process to read a CSV file into a file geodatabase. Then, I want to read this imported file and work on it by adding new fields and calculating values. However, while using the ...
2
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2answers
1k views

ToolBar icon images missing

very early build ~ zip file I am getting blank outputs for button images in a custom toolbar. Although the button information populates the dockable toolbar, they lack respective icons [see Fig.1] ...
2
votes
1answer
87 views

Finding Code in QGIS Select Features Toolset

Can anyone tell me in what directory the pre-installed Python scripts for the QGIS selection tools (i.e., Select by Point, Select by Polygon) are found? I am using on a Windows 7 installation of QGIS ...
2
votes
1answer
1k views

Determine Equal-Area Slope of Longest Water Course in Catchment

I'm still very new to python and need some direction in developing a Arcpy\Python script to determine the Equal-Area Slope of the Longest Water Course within a catchment. The Longest Water Course is a ...
2
votes
1answer
544 views

How can I extract only band 4 from a geotiff multi bands to create geotiff or AAIgrid with this band using Python?

I have a geotiff file with many bands... I will like to create a .asc file or tiff file by converting only one band from the geotiff file. I don't find the solution by using python... With ...
2
votes
2answers
544 views

Update raster value to reflect total number of points within cell- python

I have what should be a fairly simple task, but I can't seem to figure out how to do it. I have to do it in python/arcpy/gdal/whatever because I'm trying to automate this process for a hundred or so ...
2
votes
1answer
283 views

How to Format Description when writing Help for Python script tool?

I try to format the description in script tool but I don't know how it works so i don't manage to add a line break for example. Does it works with HTML tags ? When editing my script the description ...
2
votes
2answers
350 views

Why is arcpy.StackProfile_3d -> arcpy.SaveGraph_management creating empty graph?

In a python script I'm trying to save a graph to a .png file with graph output from arcpy.StackProfile_3d but the .png file shows an empty graph. The table created from arcpy.StackProfile_3d shows ...
2
votes
1answer
2k views

import qgis.core problem with QgsFeature and QgsGeometry

I've tried several previous answers to similar questions - no luck. I run Win7. I installed QGIS 2.2.0 using the OSGeo4W 32-bit installer. Problem 1) from qgis.core import * failed. Solution 1) ...
2
votes
2answers
392 views

How do I load mapinfo mid/mif into geopandas?

I suspect this is a trivial question to answer but how do I load mapinfo mid/mif files into geopandas? While it's trivial to load and manipulate .shp files, I can't work out what code to use: Here's ...
2
votes
2answers
2k views

What is the most efficient way to iterate through folders and geodatabases?

I am looking at cataloging some data, and I have code that works, it just seems to take a lot of time to run through all of the items. The way this data is structured is a bit of a hindrance, ...
2
votes
1answer
194 views

If Then Modelbuilder, Project error

I have a model where I want to check the projection. If it is GCS_WGS_1984, I want it to go one path, and if it isn't, I want it to go another path. I created a "Check Coordinates of Input" script ...
2
votes
1answer
256 views

How can i add a north arrow in QgsComposition?

I'm trying to add an svg image of north arrow in QgsComposition using this code: mapRenderer = iface.mapCanvas().mapRenderer() theComposition = QgsComposition(mapRenderer) ...
2
votes
1answer
442 views

Transferring data between spatial databases

I would like transfer spatial data from PostGIS to Oracle Spatial. I want to use Python's modules psycopg2 and cx_oracle. Transfer Oracle > PostGIS is OK, but in opposite version I have problem with a ...
2
votes
2answers
416 views

Can I use the LEFT (string) operator in ExecuteSQL()?

In QGIS I can use the LEFT operator on a dataset like this: LEFT( "Name2",3) ='031' What is the syntax for using this expression with ogr in python? Isn't this the right syntax? ...
2
votes
2answers
804 views

How to create equidistant points in QGIS along a polygon?

I am looking for a solution to distribute with a python script equidistant points in QGIS along a polygon. I tried to use the following code example: ...
2
votes
1answer
1k views

How to make autoIncrement number start with (001…009, 011…099)?

i have a challenge with my time in my work, i have feature class called "Parcel" storing many data, i generated an autoIncrement number by using field calculator, in field "parcel code" Expression: ...
2
votes
1answer
123 views

Irrational feature ID behavior in a PyQgis script

I've written a script to determine the coordinates of a point shapefile and insert them into its attribute table. It works perfectly when the ID sequence of the indiviual features begins with 0, yet ...
2
votes
1answer
463 views

Which data providers support loading attribute tables without geometry?

I have a table in Memory from a cx_Oracle query (a list of rows, and a list of field names and their types) in my python plugin and I want to load it as a geometry-less layer (Attribute table) in ...
2
votes
3answers
129 views

How to analyze and combine overlaping elevation maps into one?

I have 30 overlapping maps that contain tree density heights (measures between 1-100%) of a large area, and I need to get the highest point by pixel and create a new map with all these highest points ...
2
votes
2answers
49 views

Assigning ID to features with similar attributes

I have a polygon feature with three attribute columns. The values in each of the attribute columns are number coded. I want to generate an ID (fourth column) for the unique combination of the values ...
2
votes
1answer
948 views

How to create a symbol with graduated marker size and line width in pyQGIS?

I am using QGIS + pyQGIS + Python. Layer geometry is line. Each line has a magnitude and a direction (from 1st node to 2nd node). What exactly I want to perform is "graduated width marker symbology ...
2
votes
2answers
902 views

Find index location of a lat/lon point on a raster grid in ArcPy

This question has been confusing me for a while, and I'd love y'all's help. I'm trying to find the index location on a raster (in terms of column and row#) of a specified lat/lon point. My first ...
2
votes
1answer
447 views

How to assign values to field using if/then logic involving multiple fields?

I want to run a field calculation on a string field named [territory] that first looks at a string field [majr_src] to see if there is a value other than "NONE", if so [territory] = [majr_src]. If ...
2
votes
1answer
989 views

How to refresh Catalog window from ArcMap using Python?

I am running my script from ArcMap and I have the Catalog window open on the side. I delete some extra files in the end of my script but I have to refresh the Catalog window to see them go. So I ...
2
votes
1answer
944 views

ArcGIS 10.0 get sde information out of .mxd

The overall goal here is to iterate through several directories of .mxd files and document which SQL Server instance of SDE they are pointing to, with the database name and feature class names. All ...
2
votes
2answers
78 views

Accessing features via arcpy

i try to use arcpy to accessing the features of a shapefile. I tried to use a searcheCursor, like that: cursor = arcpy.da.SearchCursor(Points, ["SHAPE@XY"]) for row in cursor: x, y = row[0] ...
2
votes
2answers
885 views

Interpolation iteration using ArcGIS- arcpy

My current project requires interpolation of state level weather data. Approximately 5 years of daily data needs to be interpolated. I still need to figure out the best interpolation method. However, ...
2
votes
1answer
338 views

How to add ArcPy Feature Layer to ArcMap automatically?

With Python, how do I get either the MakeXYEventLayer_management or the MakeFeatureLayer_management layer that is temporarily created added to ArcMap automatically after the tool is run, without using ...