A characteristic of an object (person, thing, etc.). In the GIS field, it is used to refer to the non-spatial data associated with a location or geometry

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4
votes
2answers
2k views

How to collect data via WFS and Popup

I have a map with a WFS-Layer and I am able to add Polygons to my data stored in a PostGIS-database, served with Geoserver (Openlayers, Geoserver 2.1.4, PostGIS 2.0 for PostgreSQL 9.1).) How can I ...
10
votes
5answers
2k views

How to identify duplicate attributes in a field?

I have a point shapefile with thousand of points. It has an ID code field that supposed to be unique. Every now and then the data entry clerk wrongly type the id creating duplicates.Right now I'm ...
18
votes
3answers
3k views

How to easily edit attribute data using Regular Expressions?

I am writing a tutorial for MSc students that uses QGIS. One of the tasks requires the attribute data to be modified (see pdf draft of tutorial here if interested ). The question is how to get them ...
5
votes
1answer
998 views

Can I change properties of several layers simultaneously?

I'm working on bulk data. I have a few hundred GeoTIFF images imported into a QGIS project, and I'd like to modify their layer properties - things like the no-data-value, transparency of certain pixel ...
4
votes
1answer
1k views

What is the best way to connect spatial data with attributes in Excel table?

I have many attributes which are stored in an Excel table. They refer to USA counties. I need to somehow connect those attributes to polygons in some format (don't know which is the best) and ...
10
votes
2answers
910 views

How to compute a new attribute based on changes in another attribute?

I am attempting to classify a set of gps time-encoded point data into behaviors based on different attributes. I have created an attribute that is 0 for home and 1 for away based on location, and now ...
2
votes
1answer
266 views

Raster as Attribute Field Error

I'm using Arc 10.1. I am creating a parcel inventory where I would like to have a photo of the property attached as an attribute and view-able with an HTML popup. I have a polygon feature class built ...
6
votes
2answers
142 views

How to enumerate join values with ArcGIS?

I have two shape files (e.g. postal code areas and cities) which I want to join based on an id that both shape files have in common (the id would be the city name in this example). Joining the two ...
6
votes
2answers
5k views

How do I change the data type in attribute table in QGIS

I have county data in which the FIPs (actually State FIPS and County FIPS combined). I have data imported as CSV with the sames FIPS data titled STCounty. However, the shapefile FIPS is listed as a ...
0
votes
3answers
626 views

KML attribute data on onload of html page using openlayers

How to get KML attribute data on onload of html page using openlayers. This is kml file: click here to get kml file Any help is appreciated. Thanks in advance.
5
votes
1answer
368 views

How to programmatically associate a layer with a custom UI?

I know it is possible to associate a layer with a custom UI for editing feature attributes using the QGIS interface. But is this possible with Python? This link shows how to achieve the result ...
3
votes
0answers
2k views

How to edit Attributes on WFS Layer through Popup?

I am working on a project for university. So far I have displayed WfsLayers which can be select from a panel, also I can click on my points whereupon a Popup will show up with some information which ...
2
votes
2answers
71 views

Why OSM data has different attribute values from the same element and same time frame?

Here is my question: Does anyone know why OSM has different attribute values from the same element and same frame time? The example explains itself, when I try the Shapefile from different mirrors ...
2
votes
1answer
52 views

Compare features in PostGIS with updating attributes

I have two polygonal layers: "existing" and "modified". Attribute table of "existing" and "modified" layers have same column "feature_id" - number of feature. Please help me create query which write ...
1
vote
1answer
124 views

Adding attribute list to combobox in a python plugin

I am developing a simple plugin at the moment which contains 3 combo boxes: comboBox_1 comboBox_2 comboBox_3 Combobox 1 & 2 lists the vector layers available, however I would like the 3rd ...
6
votes
2answers
127 views

What event is fired when a feature is edited?

When the user draws a new feature (line, point, etc.) in ArcMap, there are null attributes. If the user enters values in these null fields what is the event that is fired? I want to control the ...
3
votes
1answer
69 views

New attribute creation using ogr and regex

I've got a folder full of dxf files with elevation values included as part of a long text attribute. I've written a regex expression to extract the elevation value, and would like to add it as a new ...
3
votes
1answer
985 views

Why can't I edit attribute table imported through 'text as layer'

I imported the coordinates from an Excel table. They show as single points as intended. Now I want to add columns to the attribute table, but I'm not able to edit it. I wanted to import the following ...
3
votes
1answer
89 views

Field Value Mapping QGIS

I am wondering if there is a way to do field value maps that are filtered based on another attribute field? I know how to associate value maps, but not that are connected to another field. I have ...
3
votes
1answer
577 views

How to add CSV data with no coordinates to a polygon layer in QGIS?

I would like to add attributes from an spss database (around 300 cases) to a polygon layer in QGIS. Both datasets have a column with unique IDs. I exported the spss data to a CSV file which does not ...
2
votes
2answers
400 views

Merge lines with the same 'name' attribute on QGIS?

I have a shapefile with a few thousand lines, each is a street segment. I'd like to merge all features with the same 'streetName' attribute into a single attribute. I only really care about the name ...
2
votes
0answers
149 views

Assign Sink ID to upstream features in a geometric network

Looking for a way to automatically assign an 8-character Sink ID to every upstream feature in a geometric network. There are over 500 sinks and about 5000 points and lines upstream from those sinks. ...
2
votes
2answers
2k views

How to access attribute data type in QGIS?

I've been developing a plugin on QGIS platform using PyQGIS. So far plugin does the following: You can select any feature of the already loaded vector layer in QGIS. After selection, plugin displays ...
1
vote
2answers
2k views

How to Merge/Dissolve Polygons By Common Attribute Field in QGIS?

I have joined corresponding Local Enterprise Partnerships table data into a polygon shape file containing UK Local Authorities. How do I Dissolve or Merge the the Local Authorities polygons by ...
1
vote
0answers
61 views

Network Analyst: How to sum cost attributes without length with closest facility tool

I am working on Safe Routes to School, and have created a network dataset. Each segment of the newtork has a 'walk_score' assinged (0,1,3,5,10), based upon street classification and sidwalk ...
1
vote
1answer
210 views

Connect not working for custom QGIS form

So I have a custom form for editting feature attributes. However, I can't seem to correctly disconnect and reconnect certain bindings. The init code is below and should work for any simple QT widget ...
1
vote
2answers
111 views

Generating new shp files according to attribute in QGIS

I know that it is possible to color a vector map by attribute. I separated a map into 4 colors based on an attribute and now I want to generate a new map for each color. Is there a way to do this in ...
0
votes
0answers
27 views

Is there a method to add attribute weights to a network analysis?

I would like to use demographic attributes of a census tract centroid as a weight for a closest facility analysis. My tract centroids are incidents in the analysis while medical centers are ...
0
votes
0answers
137 views

Show live attribute when hover in a map

i'm still new in openlayers. i would like to show "location" attribute on right corner of the map when hover in map. my map consist of of many attributes and one of them is location. how can i ...
0
votes
4answers
149 views

How can I calculate different polygons by different attributes?

I'm doing my master thesis and want to calculate different polygons (in QGIS 1.8 for Mac) in four different columns which I defined by different attributes. i.e. some of the attributes in the first ...
0
votes
2answers
2k views

OpenLayers Select a feature from attribute or id

Using Openlayers.....Is it possible to select a feature on a map by an attribute? eg: Select a feature from a dropdown menu populated with the feature "id" or a table field attribute values.
0
votes
0answers
28 views

Raster attribute field error [duplicate]

I am trying to add jpegs to a raster data type attribute field. I want to this field to be managed by the file geodatabase. When I load the photos and try to save my edits it get various errors but ...
0
votes
1answer
2k views

How to Obtain the feature attributes from feature collection

I am able to obtain the features of the layer which is selected by the user in the Layers table and then intersected by a user defined polygon, using e.features. I was able to obtain the attribute ...