A representation of a real-world objects on a map.

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21
votes
5answers
9k views

What is difference between map layer and spatial dataset (e.g. feature class, shapefile)?

This may be very trivial question. To me they seems very similar in concept. What is the difference between feature class and feature layer?
9
votes
3answers
3k views

What is quickest way to select polygon by point in ArcGIS 10 using ArcPy?

I keep thinking that I must be missing something, but there does not seem to be a tool in ArcGIS 10 to select features (in particular polygons) from a layer at a point (X,Y) location via ArcPy. The ...
4
votes
1answer
408 views

Need to delete all but one feature from a set of features with the same ID, keeping the one with the largest area

I have a large polygon layer in which most of the polygons have a unique name in a text field. Of the hundreds that aren't unique, there will be 2-4 polygons with the same name but different ...
1
vote
4answers
5k views

Cutting features in ArcGIS 10

What´s the easiest/smartest way of getting the opposite output of the clipping tool? I just need the area of feature A1 which is not covered by feature A2 in a new Layer/File. Now, I get the result by ...
11
votes
2answers
4k views

How to use label classes, expressions, and annotations?

I've always found that when it comes to python, vector analysis, QGIS gives ArcGIS a run for its money, hell some of the qgis plugins exceed ArcGIS's performance by a few hours; however, I always have ...
10
votes
3answers
399 views

What are some of the features available in non-FOSS GIS software that you'd like to see in your favorite FOSS GIS

For example, a program I use (TransCAD) has the ability to do travel time matrices based on minimal data input, which is really useful if you're looking at doing back of the envelope type ...
10
votes
3answers
313 views

What is a non-geographical feature?

When using the term "feature" in GIS, what is often (if not always) meant is a geographical feature which "is a representation of real world phenomenon associated with a location relative to the ...
7
votes
4answers
4k views

Get all the points of a polyline

I have some polyline feature objects in python. Now I want to get all the points of polylines. For example, if a polyline has start point [0,0] end point [5,5]. Result: ...
2
votes
1answer
343 views

QGIS identify features button issue

Is there anyway to get the Identify Features button in QGIS to automatically select a layer and provide the information without having to highlight it first in the layers TOC? MapInfo and ArcGIS ...
5
votes
3answers
341 views

Selecting polygons by number of sides

I'm using ArcGIS 10 to build some figures for a journal article. One is a figure of an unstructured finite element mesh of triangles spanning the western Atlantic Ocean. I exported this mesh from ...
3
votes
2answers
734 views

Replicating ArcMap's Point Sketch Geometry Editing (Feature Templates) in ArcObjects

I'm looking for a way to place, select, move, delete features inside a custom C# ArcObjects application (using AxMapControl). I found the exact behavior in ArcMap, but I want to save the user some ...
2
votes
3answers
592 views

how to change color of feature to mark it as recently modified with openlayers

I am developing a crowd sourced app using openlayers. after user clicks an feature, a popup form is displayed. After clicking the save button, the data is used in processing which takes some time so ...
6
votes
2answers
121 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 ...
4
votes
2answers
202 views

How to find out what features /tags are included in an .osm or .pbf file?

I would like to load osm data into a postgis (postgresql) database. In How to load OSM data into PostGIS preserving all Tags? there has been a solution posted: Download the OSM files (in .osm ...
4
votes
3answers
3k views

How can I unselect a feature in Openlayers?

I am able to identify the selected features on my map using the following line: vector_layer.selectedFeatures I would like to be able to deselect this feature using a standalone function (not an ...
4
votes
3answers
458 views

Can I prevent features from being created outside an OpenLayers map?

In our app, we allow users to create features on maps. The boundaries of these features will later be converted into real-life latitude/longitude coordinates, but does not make sense if features are ...
4
votes
1answer
6k views

How to get features in Openlayers vector layer

What is the exact API to get all features in a vector layer in OpenLayers? Suppose I have the "map" object, within which is a "Vector Layer": how can I obtain features in the layer?
3
votes
2answers
2k views

How to create a feature class in a file geodatabase in ArcGIS 9.3 with Python?

I'm not entirely sure if I am using the correct terminology, so I apologize in advance. What I am looking to do is create a file geodatabase and add a feature class directly into that file ...
1
vote
1answer
574 views

Overlaping graphics not visible in featureLayer

I have constructed featureCollection from Json and feature collection has 44 features. I have given this feature collection as input to the Featurelayer which is showing only 32 graphics objects of ...
1
vote
2answers
1k views

“Item not found in this collection” when trying to set the Shape on IFeatureBuffer

I'm working on code to open a 3rd party data file and convert it into a collection of features in a custom layer based on FeatureLayer. I have had no issue importing the data itself (nodal data for ...
0
votes
4answers
2k views

How to Clip a Shapefile of Circle features using a Raster using ArcGIS 10

I want to keep all the features in the shapefile that lie in the raster region and reject others. How do i do this? ------Adding More Details-------- Data to be Clipped: Is A Shapefile of 1 mile ...