2
votes
0answers
15 views

Create network graph from contiguous polygons in KML, or PostGIS?

I am using Postgres 9.5 and PostGIS. I have a table with a geometry field. This table has about 200 rows, in each of which the geometry field contains a Polygon. I would now like to derive an ...
0
votes
1answer
26 views

Select by location and copy features to new shapefile

I have been asked to select point features that fall into a polygon in its own shapefile then copy the points selected to a new shapefile. There are around 300 shapefiles with an indiviidual polygon. ...
0
votes
1answer
19 views

Problem with read_shp() in NetworkX

I'm trying to convert a shapefile of only line geometry (a street network) to a NetworkX graph to run some connectivity algorithms on it. I'm running into this issue: File ...
0
votes
0answers
9 views

Why do I get incomplete answers using google maps api in java?

I'm using google maps API in java to check wether some places are correct, but I don't get all possible responses: GeocodingApiRequest req = GeocodingApi.newRequest(context).address("Sydney"); try { ...
1
vote
1answer
19 views

Syntax error in a query with ST_AsText and ST_CENTROID

I have a table in a PostGIS database where with this query : SELECT ST_CENTROID(pol8.geom) AS geom FROM polygon8 AS pol8; I got this: geom ...
-1
votes
0answers
18 views

Important and relevant GIS mailers or electronic newsletters [on hold]

What GIS mailers if any should a GIS Professional working in USA county government subscribe to? I am concerned with staying on top of relevant technology, meta GIS topics, and educational ...
5
votes
1answer
62 views

1-center and k-center problem / maxmin facility problem in Post

is there anybody who has already solved the 1- and k-center problem within PostGIS (optionally with distance metric obtained by pgrouting)? References: 1-center problem in Wikipedia and graph ...
1
vote
2answers
46 views

Rasterizing polygons with the function “gdal_rasterize” in R

I'm using the function gdal_rasterize in R (package gdalUtils) to convert a polygon shapefile into a raster. Here is my code: r.test <- gdal_rasterize(src_datasource="df.shp", ...
2
votes
1answer
416 views

How do I center a custom control in Openlayers 3 horizontally?

Ok, this is more like a CSS question than a GIS one. But I don't have any clue how to center an element that has an absolute position. Edit 2015/05/29: Here's some relevant markup for my icon ...
2
votes
1answer
32 views

Get the same coordinates for points after downloading a .osm file

I downloaded a .kml file that contains bike stations which I know the coordinates (latitude and longitude). So I got a layer that contains points corresponding to the stations. Then I downloaded the ...
1
vote
1answer
15 views

Error distance for coordinate transformation (to WGS84)

I have a dataset with mostly EPSG:31255 and wanted to convert it to WGS84. I now had to realize that the results are up to 100m off when I plot them on a map or just enter the resulting lat lon in ...
0
votes
0answers
4 views

QGIS-server, WMS, layer-providers

QGIS-server is running on Ubuntu 14.04. I´ve tested with adding shp-layers to my project, but won´t be listed when conncected to the wms for the project. Adding layers via postgis-provider, it works ...
3
votes
2answers
428 views

Plotting X, Y coordinates generated from MySQL database in QGIS

Currently running QGIS 1.8.0 on Mac OS X 10.8.4. I can plot points on a map using the "Add delimited text layer" plugin to get x-y coordinates from a text file. However, I'd like to be able to ...
1
vote
1answer
32 views

Coordinates are wrong

I thought that I solved my problem, but I am just facing another one. In the QGIS 2.13.2 version I have a google map and a shapefile. Now I want to print it with all the necessary items, but I have ...
1
vote
3answers
687 views

GeoAlchemy: AttributeError: type object 'ColumnProperty' has no attribute 'ColumnComparator'

I installed GeoAlchemy using easy_install but when trying to import it returns the following: Traceback (most recent call last): File "", line 1, in import geoalchemy File ...
2
votes
1answer
35 views

How to create a two sided ticks labels grid in layout (ArcMap)?

I'm making a planing map. I want to add to the final layout a specific kind of grid: The grid needs to be with a 6 character label that is separated in to two labels. Each one of the labels needs to ...
7
votes
1answer
2k views

Counting number of points in a point shapefile - ArcGIS 10.0 / arcpy

I assumed this would be an easy thing to do. I'm loading a point shapefile into a map like this: layer = arcpy.mapping.Layer(file_name) Is there a way to get the number of points in the shapefile? ...
0
votes
1answer
11 views

Uncaught TypeError: registry.forEach is not a function

I am trying to add two dojo buttons for polyline and rectangle on a map, and i have written loop for two buttons, but i am getting error :"Uncaught TypeError: registry.forEach is not a function" ...
1
vote
1answer
2k views

Creating MySQL database for storing imported KML?

I need to create a MySQL database for storing coordinates from a KML file with the structure as follows: <Placemark> <name>someplace</name> ...
5
votes
3answers
8k views

Geoserver/java out of heap space - how do I increase it?

I'm new to Geoserver, Ubuntu and Java, but have downloaded a virtual machine from gisvm.com and am getting up to speed. I got as far as configuring it with some fairly large shapefiles from a project ...
1
vote
0answers
10 views

Retrieve available PostGIS connections in PyQGIS

Can I retrieve the available connections to PostGIS databases in PyQGIS? I would like to provide a list of available db-connections, and subsequently a list of tables within the ui of my plugin. I ...
1
vote
0answers
22 views

Spatial Join - Field mapping to delete and rename fields

I have a python script where the user can enter a study area (Polygon shapefile) and multiple point Features of interest (Point shapefiles). The point shapefiles are looped through and joined with ...
1
vote
0answers
14 views

Geoserver WFS Layer in OL3 tilted and mirrored

I am using Geoserver (2.4.2) to display a WFS-Layer in Ol3 (3.13.0). I successfully used this example from a fellow user to get things going. Here is my modified code. I am sorry for not providing a ...
1
vote
1answer
15 views

Spatial join for multiple shapefiles (loop)

I have the following two datasets: - polygon shapefile containing administrative boundaries of a City - multiple point shapefiles What I want to do is to spatially join the point shapefiles with ...
0
votes
0answers
6 views

Open Layer 3 SecurityError: The operation is insecure (CORS problem?) [duplicate]

I have a very simple OL3 application. I am reading in a WMS layer from a local Apache webserver on port 444 which is being served from a geoserver via Tomcat 7.0.51 on port 8443. All is fine, ...
0
votes
0answers
5 views

Grid parameter restriction of mpl_toolkits.basemap.maskoceans

I have plotted the image below with the use of matplotlib and mpl_toolkits.basemap. However I am not satisfied with the result. The image is still very blocky near the coast line. The grid parameter ...
0
votes
1answer
39 views

Geosearch Esri controls in leaflet

It is possible to disable the Geosearch Esri controls in leaflet after the first geocode search? When I run Chrome console and I select the search geocode icon this is the code: <input ...
1
vote
1answer
43 views

Average stationary position with GPS

Is it possible to average a stationary position with a GNSS (GPS, GLONASS...) with a centimeter accuracy without external corrections (like differential or RTK)? If so, how long does such averaging ...
3
votes
1answer
336 views

Geoserver installed but some components not working

I have installed Geoserver 2.6 on windows 7 32 bit os. Java version is 7. First: installed with installer.exe Second: installed tomcat8 and web archive I installed two way. But some components are ...
0
votes
0answers
9 views

RPC calculation?

I wonder how RPCs are created for satellite images. I read that RPCs are used to correct for systematic error in the image which arise due to Surface relief, camera orientation wrt nadir, camera tilt ...
2
votes
2answers
56 views

AttributeError: 'Layer' object has no attribute 'listLayers'

I want to use the result of OD cost matrix for my further calculations. However, whne I try to extract the sublayer "lines" it returnes an error AttributeError: 'Layer' object has no attribute ...
1
vote
1answer
11 views

Creating composite band mosaic of sentinel 2 data with arcpy

I previously useda simple script that went through many Landsat satellite images, and for each folder it found it made a composite band raster. The script was as follows: import arcpy import os ...
1
vote
1answer
21 views

Is there a way to create a presence/absence matrix of polygons per cell in a grid using qGIS?

I'm working in QGIS with species distribution polygons and I want to know how many cells in a grid does the polygon overlap. I've tried creating random points within the polygon and then used ...
2
votes
0answers
7 views

In QGIS 2.12 processing R scripts fails (plots remain blank) due to a wrong variable name - Is there a workaround?

I am trying to execute r scripts in 2.12. All of them fail. Plots remain blank. It seems that the variable "Layer[[Field]]" returns NULL: E.g: hist(Layer[[Field]],main=paste("Histogram ...
1
vote
1answer
24 views

Is it possible to change the precision of a field in the attribute table in ArcMap? [duplicate]

Is it possible to change the precision of a field in the attribute table in ArcMap? I have a shapefile with X and y coordinates of pointlocations. I would like to change the precision. Is this ...
5
votes
4answers
433 views

Is there a way to close a geoprocessing operation when the dialog box has been hidden/pushed to the back of the window

Is there a way to close a geoprocessing operation when the dialog box has been hidden/pushed to the back of the windows? I ran a python process as VB Script and when the error message appeared I ...
2
votes
1answer
47 views

How to create a shapefile from xy in .csv file?

I find many difficult to create a new shapefile in a new project following those steps. I think the .csv file is correct (there are only: ID, X coord, Y coord) but when I would create the shapefile ...
6
votes
1answer
597 views

Grouping of layer with GeoServer and OpenLayers

I need help to display layers group/non group 1. with checkbox to select layer or group 2. icon/symbol for each layer. I saw example codes from OpenLayers where it's adding the layers statically. ...
1
vote
0answers
6 views

mod-tile: How to set up two independent tileservers?

Reading mod-tile and rendered documentation, especially the commented lines in the renderd.conf file, it seems to be possible, with the same renderd and mod-tile, to define two different style sheets ...
0
votes
0answers
10 views

Maximum Likelihood Classification in ENVI

can anyone help me? I am a new ENVI user and I am trying to perform a supervised classification of a Landsat 8 image with the maximum likelihood algorithm. In order to run the classification, I have ...
2
votes
0answers
15 views

Pre-processing in remote sensing [duplicate]

I have a bit of confusion on the pre-processing of remote sensed images. Do atmospheric correction methods such as Dark Object Subtraction convert the DN into reflectance values? If not, it is ...
21
votes
8answers
2k views

How to generate a random but believable digital elevation model?

Is there a way to generate a DEM, programatically or otherwise (arcpy or R?), that will feed into ArcGIS for further spatial analysis? Perhaps this needs to be broken down into smaller incremental ...
0
votes
1answer
13 views

set up transport modes osrm

I wondered if anyone could help. I have setup osrm on a spare computer it is running on Ubuntu 14. It works fine and I can query it using the default car setting for transport. I would like to be able ...
0
votes
0answers
16 views

Calculate obstacle accountability area in QGIS

Still being new to the whole GIS world, I am trying to calculate a regulatory takeoff obstacle accountability area for a given runway. For my case, this is defined as an area as follows. At the start ...
4
votes
1answer
104 views

Difference Between Radiometric calibration and radiometric correction

I am new in remote sensing field. I sometimes got confused when I read about image pre-processing. Can someone please elaborate to me the difference and some example methods to do radiometric ...
1
vote
1answer
13 views

Port Number GeoServer to OpenLayers map

It is necessary to use port number like 8080. Is it not work with port number.
0
votes
1answer
190 views

grass - add on problem

I can't install the addon in grass 6.4.3 to my linux mint. i've already installed the SVN and than it says: GRASS 6.4.3 (fabian_idrisi):~ > g.extension r.fuzzy Fetching from GRASS-Addons SVN (be ...
0
votes
1answer
18 views

Developing android app for map interaction [on hold]

I'm looking for technologies for making android widget for which can computationally effective display large map. My question differs from analogues in that I seek for principal technologies (not ...
4
votes
1answer
67 views

New field names after joining 2 tables in QGIS

When joining two files (A.csv and B.shp with a common unique ID) in QGIS the new fields in B.shp (from A.txt) include the name of the field + the name of the file where it comes from (A). For example ...
2
votes
1answer
38 views

snapping line nodes to points

I have a dataset of manholes and pipes; I want to snap the lines start and end nodes to the manholes if they are within a specified distance. Been trying to find away to do this using PostGIS or QGIS ...

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