Python is an open source interpreted programming language used in many GIS programs.
5
votes
2answers
87 views
How to do advanced Python labeling in Arcmap?
Does anyone have a good reference for advanced/complicated labeling expressions in Arcmap? I am attempting to write a Python label expression that would involve multiple label definitions.
Here is ...
3
votes
2answers
62 views
How to computational efficiently check if there are any overlapping polygons in a group of polygons?
I need to do some processing with groups of polygons. If any of the polygons in the group overlaps other polygon the result is unpredictable and don't throw any error. So, I need to detect if there is ...
1
vote
2answers
57 views
ArcMap label expressions with Python
Having trouble here: I'm trying to use python to write selective label expressions. I have several concentrations and depending on its "_Ex" number I either want it labeled red, not red, or not ...
-1
votes
1answer
58 views
QGIS and Python - create line with multiple points in postgis
How can I create a line, with Python functions, with many points that are records in Postgis?
Thank you
6
votes
2answers
92 views
Refresh open attribute table in ArcMap (arcpy)
I am running the Calculate Field GP tool from the arcpy in ArcMap. When a row value is updated, it does not show up untill I use the Reload Cache tool (Table Options > Reload Cache). How do I refresh ...
1
vote
1answer
79 views
Search cursor stops selecting after two iterations
I have a script which selects an extent from a grid and exports the data frame.
import os, arcpy
mxd = arcpy.mapping.MapDocument('CURRENT')
df = arcpy.mapping.ListDataFrames(mxd,"Layers")[0]
...
4
votes
1answer
40 views
Using matplotlib to create and export graphs automatically from ArcMap
I am going to start a project soon where, after the data has been processed in various ways, an output jpg showing a graph of the data should be produced. The workflow is as follows:
1. A feature ...
0
votes
1answer
60 views
Use subprocess.call with gdalwrap
I am now want to use subprocess.call with gdalwrap to clip raster from shapfile
(in qgis 1.8.0)
I use raster→projections→wrap(reproject)to generate command_line below
gdalwarp -t_srs "+proj=tmerc ...
2
votes
0answers
72 views
How to interpolate GPS data correctly?
I'm working on a project that involves using linear interpolation to fit lines to
lat/lng points. I'm pretty new at scientific programming related stuff, and I was wondering if people could steer me ...
0
votes
2answers
51 views
Splitting Shapefiles [duplicate]
I am trying to create a code that will accept the input of a shapefile, and separate each of its features into separate shapefiles into a specified directory location. Can anyone help ? I am trying to ...
6
votes
3answers
109 views
How to efficiently read and reclassify many rasters in R
I've been tasked to create a suitability analysis of wave conditions in the Gulf of Mexico. I have 2 thousand or so raster files that are about 8 MB each (2438 columns, 1749 rows, 1km cell size). ...
0
votes
1answer
51 views
AttributeError: HelloWorld instance has no attribute 'connect'
Here's the code:
import sys,os
import win32api
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core import *
import ctypes
from PyQt4 import uic
class HelloWorld:
def ...
1
vote
1answer
58 views
How to get point x and y geometry from a shapefile?
I have a shapefile of US Cities and I want to get the X and Y coordinate of EACH city in that shapefile. I've tried this:
for city in city_cursor:
geom = city.Shape
point = geom.getPart()
...
1
vote
2answers
101 views
Can anyone recommend an Arcpy GUI? [duplicate]
Alright I have been having really good luck with you guys so here is my question...
Can anyone recommend a GUI for arcpy? So if I want to run my script as an exe with some blank text boxes(or text ...
1
vote
0answers
25 views
Problems running zonal statistics - not all zones represented
I have been working on a Python script to automate the steps illustrated by whuber here:Create points around the edge of viewshed results
I am trying to create a horizon graph illustrating the ...
2
votes
1answer
88 views
How to calculate volume from a raster file?
I have a raster file containing the depth of water. I need to find the volume of water using that raster file. I need to find the area of each cell and multiply with the depth. How can I do it in ...
-1
votes
0answers
25 views
How to use sub queries while inserting record into db using cx_Oracle in python? [closed]
I need to add a symbol with the value of self.wrkArea variable like this
(select chr(182) from dual) || self.wrkArea || (select chr(182) from dual)
i.e. ¶workarea¶ will be the result. how to ...
0
votes
1answer
52 views
How to buffer increasing/decreasing population zones?
I will find out the difference in population between year 2000 and 2013. I have a feature class file with the population in year 2000 and 2013 that are connected to the municipal number and that is a ...
2
votes
1answer
63 views
How to write point geometries with arcpy instead of gp syntax?
Can someone help me fix some code that simply writes points into a featureclass? It used to work in the older gp. syntax, but I'm having difficulties rewriting it in arcpy for ArcGIS 10.0. In this ...
2
votes
1answer
43 views
Exporting Selection Using Python
I currently have a search cursor iterating through a shapefile in ArcGIS 10.1 that selects a feature and runs a viewshed analysis on that feature (and only that feature).
What's the easiest way to ...
1
vote
0answers
20 views
Calculate complete spatial randomness using Python [duplicate]
I currently use the csr() function from Splancs for R (http://cran.r-project.org/web/packages/splancs/splancs.pdf) to calculate complete spatial randomness (CSR) points to be used for spatial ...
0
votes
1answer
49 views
How to set Marker Line symbol for QgsVectorLayer by using Python?
QgsVectorLayer Right click->Properties->Style->Single symbol->click on simple line in tree node ->symbol layer type -> Marker line
Kindly help me to set marker line symbol programmatically by using ...
1
vote
2answers
61 views
How to Add Shapefile with Symbology from Layer File to ArcMap MXD using ArcPy/Python?
Say I have a Shapefile:
C:\DATA\points.shp
A layer file:
C:\SYMBOLOGY\symbology.lyr
And a map document:
C:\MAPS\map.mxd
How can I add points.shp to map.mxd with the properties of symbology.lyr ...
0
votes
1answer
42 views
psexec remote file execution with ArcGIS Server
This is perhaps going a bit out of bounds, so i'm not confident I'll get an answer. The short of this is that I've created a python script which leverages psexec to start a bat file on a remote ...
3
votes
1answer
52 views
Why is my simple arcpy script failing? (sets raster cell value to null if below threshold value, ArcGIS 10.1)
As mentioned in the title, simple script to set null cell values below three standard deviations beyond the mean:
import arcpy, sys, os
#Accept input and output raster
inRas = sys.argv[1]
outRas = ...
2
votes
2answers
86 views
Help with Python and adding a grouplayer to arc, renaming it from a folder name, then adding layers to it from that folder
I am trying to use os.walk to go through a directory tree, pull out all the .shp files in it, create a grouplayer in the mxd, rename the grouplayer the folder name, then add the layers from that ...
2
votes
2answers
46 views
Raster format to read with python
I currently have a DEM raster stored in an ESRI geodatabase. I've been asked to create a purely python (e.g., no arcpy functions) program that works with the values. Therefore, I need to convert the ...
1
vote
1answer
59 views
A simple Python Script to save the currently opened mxd and changes
Here is what I have so far...
import arcpy
import arcpy.mapping as map
mxd = map.MapDocument()
mxd.save()
And yes I know that map.MapDocument requires an argument, but I want it to automatically ...
1
vote
0answers
69 views
How to embed a PDF into an Excel spreadsheet? [closed]
This is what I want to do:
Create report using a polygon feature class to output areas of polygons using some logic and the ExportReport() function (This I have accomplished)
Create a PDF of the ...
0
votes
1answer
35 views
Maintain 8-bit pixel depth in Raster Calculator
Would anyone know how to maintain 8-bit pixels when computing raster calculations in ArcMap?
2
votes
1answer
45 views
How can I set the settings of an Address Locator within a Model or arcpy?
I am creating a model that processes a large road dataset, then creates an address locator from the roads. The Create Address Locator tool does not allow me to set options like Spelling Sensitivity or ...
1
vote
1answer
52 views
How to get an attribute of the selected feature and pass it into a URL?
As a total Novice with Python, I thought 2 weeks would be enough time to learn how to build some tools for our GIS... I was wrong and I'm running up on a deadline.
I am attempting to get a value ...
0
votes
0answers
32 views
Missing SIP Module in QGIS on Debian Squeeze
Python environment is not loading and shows this error:
Traceback (most recent call last):
File "", line 1, in
ImportError: No module named sip
Versión de Python:
2.6.6 (r266:84292, Dec 26 2010, ...
0
votes
2answers
68 views
How to make line with arrow head in QgsVectorLayer using python?
I need to draw line with arrow head or after drawn the line i need to make it as arrow head line by using python. or can we set any arrow head symbol for line features by using python?
Kindly help me ...
0
votes
1answer
33 views
How can I avoid UnicodeEncodeError when using geoprocessing tools in QGIS?
I have a shapefile, that I want to split with the "Split Layers by Field"-tool. Due to some umlauts (ä,ü,ö) there will be a python error as soon, as the tool reaches a feature with an umlaut. The ...
1
vote
1answer
92 views
Creating prepared geometries with OGR from Python
Is it possible to create a prepared geometry object using the Python SWIG geos.ogr module? It seems that Shapely and GeoDjango both have this functionality, but I can't see any mention of it in the ...
1
vote
1answer
60 views
GDAL bindings problem with ArcMap 10.1 Python tool
I'm really getting mad with this. ArcGIS sometimes can be so just...irritating!
Forgive me if this question is by any means duplicating this one or similar ones, but I really can't find my way out of ...
0
votes
1answer
53 views
python script in modelbuilder: get field value and return boolean expressions
I have problems integrating a python script in a modelbuilder tool. I'm a absolute beginner with python. Maybe there's also an easier way to solve this problem in modelbuilder without using a python ...
0
votes
0answers
18 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
votes
1answer
49 views
How to find locations for hydro power using raster analysis?
I have a stream network and DEM file both in raster format. I need to extract values from DEM to stream network. For the analysis in stream network after that, I need to find out the places for hydro ...
0
votes
0answers
54 views
How to use more than one QT form in Qgis Python? [closed]
I need a help to use multiple qt forms in PyQgis. For example, i need to open one qt form after the login form.
I tried like this:
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core ...
0
votes
1answer
31 views
How to Average neighboring county data and store in original?
I have data for several rain stations, i have averaged the data and given each county a value. Some counties have null values and I would like to pull the data from the all the bordering counties and ...
2
votes
1answer
63 views
How to access the road graph plugin in python?
I am developing a few scripts in Python for QGIS 1.8 to automate some geo-tasks and one of them would be to calculate the shortest distance from a hospital to each building in a town.
I would like to ...
0
votes
1answer
66 views
Is it possible to use GDAL to combine (rather than mosaic) rasters
Is there a GDAL command which can combine multiple rasters so that a unique output value is assigned to each unique combination of input values, like the combine command in ArcGIS?
gdal_merge seems ...
-3
votes
2answers
82 views
What does Runtime error : 'NoneType' object has no attribute '<field_name>' mean?
Here is my code
#arcpy
import arcpy,sys
from arcpy import env
env=r"C:\Users\Jaya\Desktop\python_practice"
totalRec=arcpy.GetCount_management("river")
rows=arcpy.SearchCursor("river")
...
0
votes
0answers
42 views
qgis python app how to add edit feature button?
I'd like to develop a QGIS Python app for plotting points and editing the attributes. I've started with the tutorials here: http://blog.qgis.org/?q=node/59 and read the cookbook ...
1
vote
2answers
76 views
Raster Calculator question for Multiple Rasters
I am having trouble for writing script in Python (ArcGIS 10.1). The task is generally divide each raster by 100. I have many of these raster files....
So what I've done is the following:
from ...
3
votes
1answer
46 views
TKinter to provide variables
I've been looking for a way to enter a unique field name into an attribute table for up to 40 feature classes. I need the field names to be meaningful, not just 'field1', 'field2' etc. For example, if ...
3
votes
1answer
103 views
Python Script for getting elevation difference between two points
I have several stream segments 1000 Km long. I need to find the elevation difference between two consecutive points of distance 1 Km starting from the upstream to downstream. How can I get the ...
5
votes
1answer
103 views
How to create a dropdown menu in QGIS Toolbar with Python
I Have a set of some QAction in my QGIS-Plugin and they are created and added to the toolbar like this
icon = QIcon(":/action1.png")
self.action1 = QAction(icon, u"Action 1", self.iface.mainWindow())
...
