A geometric element defined by a pair of x,y coordinates.

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1
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2answers
555 views

Is there a way to have a single point feature with multiple records?

Is there a way to have a single point feature and have multiple attributes records associated with it? Multipoint approach won't work as it gives me one attribute set (database row). I am trying to ...
3
votes
2answers
2k views

How to easily enter a point feature in ArcGIS? (arcmap10)

My job requires me to enter point features into ArcGIS 10 which correlate to underground RFID markers that mark underground telecom infrastructure. Right now, the workflow requires someone to go out, ...
2
votes
2answers
2k views

How to automate point-in-polygon queries in ArcView?

Layer1 = point shapefile (multiple points, geocoded) Layer2 = polygon (1 attribute; (1,2,3...)) I want a non-gis person to be able input a single address and be told the attribute of the polygon ...
5
votes
3answers
226 views

Methods for lat/lon quality control?

I have a database with fields including latitude, longitude, city, state, and country. When mapped, it is clear that a number of the sites are in the wrong location - most commonly because of a sign ...
3
votes
2answers
696 views

How to loop through an array of point features?

I have a set of point features and I wish to find the points that have common coordinates. Now I changed the code as shwon bewlo by using the IPoint and the compare method through a function. I have 2 ...
1
vote
0answers
367 views

Moving GPS Points with a VB script - Bearing works well but distance is wrong

I am using a script I found online created in 2003 by one of the commentators here. It is a great script and exactly what I have been looking for and I'm very glad to have found it. It simply takes ...
6
votes
2answers
1k views

Easily find centre point of a raster in ArcMap 10 document?

If I have, say, a rectangular and georeferenced raster file loaded in an ArcMap 10 document (.tiff w/ associated tfw), how do I easily find its centre point and store that point in a points vector ...
8
votes
2answers
1k views

PostGIS raster value of a lat/lon point

I have a tiff raster in my PostGIS 2.0 database. I want to get the value of the raster at a specified lat/lon point. I have: postgresql-9.1 postgis-2.0-svn with raster support a raster imported ...
2
votes
1answer
710 views

What are nodes in ArcGIS and how do you create them?

I want to create a elevation profile of a cross section so a polyline on ArcGIS. I wanted to regularly space around 1000 points per 1700m long xsection and extract elevation data for each node/point ...
6
votes
2answers
422 views

How to Match Point Data in QGIS?

How do I match the same points (WGS84) in two different point layers? I want to get the points that lie exactly upon each other in the two datasets.
12
votes
4answers
4k 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
2answers
1k views

Problem creating a point IFeatureClass

I'm trying to create a point IFeatureClass, but my code doesn't work. Public Function CreatePointFeatureClass(ByVal featureClassName As String, _ ByVal ...
7
votes
2answers
3k views

PostGIS: Find points that lie within a set of coordinates

I have a PostGIS db, and I want to find the points that lie within some region (a bounding box). I have two sets of coordinates, from which I can get all four rectangle points that form the box (if ...
2
votes
1answer
109 views

Access points with PostGIS

I have a PostGIS table with linestring geometries and point (A) on it and I need to detrimine points (M) which located M meters from A. Distance is measured along linestrings. Any thoughts?
2
votes
2answers
180 views

Stacked point representation in KMLs

I cross posted this in the Google Earth forum but they changed the format there and I'm not sure I like the format. In my dataset I sometimes have multiple locations at a single point. GE will ...
12
votes
3answers
4k views

How to join attributes from nearest point in QGIS?

I have two layers with points, call them A and B, each with different attributes. For each point in A I want to join all the attributes from the nearest point in B. Ideally this would also include ...
1
vote
2answers
2k views

Select points within a given distance from a selected point

What I want to do: In ArcMap, let the user select a point (not a point pre-enter) and enter a range (like a Message BOX can enter range) the point (pre-enter the data and XY) within range will be ...
4
votes
4answers
2k views

How to determine a point lays within a polyline in arc engine?

I recently asked a similiar question on this, however I needed to know if there is a way to solve this if I only have a IPolyline Feature, and not the whole layer. I want to know if I can determine ...
5
votes
2answers
565 views

Does anyone know a function to determine if a Point lies on a polyline?

ArcEngine 10 .Net 4 c# Hi I'm currently allowing user to select a point on a polyline and creating a point on the line. I am using snapping tool. I just want to make sure that when the user clicks ...
4
votes
2answers
2k views

How can I compare two point shapefiles that contain lat/longs and compute distance?

Greetings everyone, I have 2 sets of point shapefiles in ArcGIS (group A and B), each set has around 1000 entries that contain lat/long. What I want to do is compare Group A against Group B and figure ...
8
votes
6answers
17k views

ERROR 000212: Cannot create XY event source Failed to execute (MakeXYEventLayer)?

I have a csv file that is 133mb in size and has over 1.3 million lines of data. Each line of data has its own lat/long and I was wondering what would be the best way to display those points based off ...
2
votes
2answers
902 views

script to create points in interval 0.125 decimal degree

I have a polygon shapefile. I want to create points at an interval of 0.125 decimal degrees in this polygon. How can I create a script with python in ArcGIS 10 to automate the process of create ...
2
votes
3answers
6k views

Change number of decimal digits for features in ArcGIS 10?

I am editing vertices in polygons and points in ArcMap 10, and realised that they only hold 3 decimal digits for the X, Y coordinates, but I would like at least 6 decimal digits. Even if I type in ...
6
votes
3answers
835 views

Converting point data into a weighted raster

I am completely re-writing my question as i think it was quite confusing before: I have a number of different points, each point has a -z value. I need to create some sort of raster or a series of ...
1
vote
2answers
3k views

Hyperlink relative paths to files in points layer in QGIS?

I would like to add hyperlinks to each point in a points layer in QGIS 1.7.0 running on Mac OS X 10.6.7, but I have several requirements: (1) Each hyperlink has to be a relative path to the linked ...
7
votes
3answers
3k views

Label points at regular intervals using ArcGIS for Desktop?

I'm working with lines on roads represented by a large number of sequencial points. Since labeling all of them would make the points impossible to identify, I'd like to know if there is a way to label ...
1
vote
0answers
274 views

getting the correct location data with user input

I have some code others have provided, which I modified in order to run a Python script in a toolbox in ArcMap which accepts user input for a starting point, distance, and angle to create a shapefile ...
2
votes
1answer
7k views

Export list of coordinates in a points layer to spreadsheet?

This is similar to my previous question, but I would like to ask it for ArcGIS, instead of QGIS. If I am supposed to somehow merge the questions, please let me know. With an existing point feature ...
17
votes
5answers
21k views

Get list of coordinates for points in a layer?

I've got a layer in QGIS that is comprised of points. Its attribute table doesn't have (show) the corresponding x and y coordinates for each point. Is there a way for me to extract a list of ...
1
vote
2answers
700 views

Error adding buffer to polyline in ArcMap 10

As the next step to what I did in this previous question, I would like to add a buffer to a polyline, with 5 meters on either side. I tried adding buffer to two versions of the line, one in ...
4
votes
5answers
21k views

How to connect points with a polyline in ArcMap 10?

I have a layer containing a few hundred points representing a survey track. The points are laid out in chronological order in the corresponding attribute table. How can I have ArcMap 10 automatically ...
8
votes
2answers
2k views

Creating evenly distributed points within an irregular boundary

I need to create an evenly distributed series of points within a series of oddly shapped polygons (formerly squares, but now squares with donut holes). The way I have solved this problem so far is to ...
1
vote
3answers
524 views

Point to Raster Issues

I am having some trouble with something fairly simple.. I am creating a 3D subsoil model for display in arcscene - i can get it displayed nicely as points but in order for the model to be easier to ...
7
votes
2answers
1k views

For a given feature find the closest point along a given path

Looking for a Java based (foss4g) solution for the following: I am using a path along with a buffer to find features that are along the path. For each of the features returned I want to find the ...
11
votes
5answers
14k views

Finding distance of point along polyline?

We need to find the distance of a series of point along a given polyline. We have a polyline dataset repsenting rivers in a catchment, broken up into river reaches (FID 1 through 35 for example). We ...
6
votes
1answer
617 views

Interpolation: irregular shape, merging DEM's

my problem is quite complex, though I hope that solution may be simple or at least possible. I do have .img DEM 0.5x0.5m. DEM consists of river bed, river valley and adjacent areas (it is strip of ...
3
votes
3answers
756 views

Spatial Database Design (PostGIS) - Point data that doesn't always have spatial data

I am creating a spatial database using PostGIS. I am storing the attributes and location of some species records that can be represented as points. The records are recorded from either: a) static ...
15
votes
4answers
1k views

algorithm to place maximum number of points within constrained area at a minimum spacing

I have a polygon layer that describes a constraint; I wish to add points within this area. I want to add as many points as possible, but they must have a minimum spacing between them. Is it possible ...
25
votes
7answers
4k views

How to compare two spatial point patterns?

If I have two point pattern distributions within the same geographic region, how would I go about visually and quantitatively comparing those two distributions? Also assume I have many points within ...
2
votes
2answers
1k views

how trace polyline between two points?(Esri)

How i can draw a line between two points...e.g.: I have initial point and endpoint and i need trace a line between this points...how i can do that?
2
votes
2answers
522 views

wkb/wkt according to OGC

how can i store my coordinates in wkb.. i want to know its implementation of wkb and wkt in db .. any one can please guide me.
6
votes
9answers
9k views

ArcGIS: Create a line layer from a point layer and csv data file

UPDATED DECEMBER 20 I have a Regular point layer and a csv file that has the same ids as the point layer. The csv file is organized as ID From To Weight -- ---- -- ------ 01 ...
7
votes
7answers
4k views

Extract raster values at points

How can I extract values from a raster by points. I prefer not in Arcgis. I prefer in Qgis or Mapwindow or other open source gis.
11
votes
7answers
372 views

Public reprojection services

Are there any free public services where I can send one point in a coordsystem and it returns the point reprojected in a specified coordinate system? I will not be doing many requests, for now it is ...
3
votes
3answers
1k views

Is there a way to “disperse markers” across multiple point layers?

I have a bunch of point layers which often have overlapping features. The disperse markers geoprocessing tool works within a layer but is there a way to do it across more than one layer, so none of ...
2
votes
3answers
314 views

UK National Grid references and GeoDjango

Newbie question. I'm trying to insert some UK National Grid references into a Django PointField defined as follows: oscode = models.PointField(srid=27700, null=True, blank=True) My question is ...
16
votes
2answers
4k views

How can I find a point inside a polygon in PostGIS?

How can I find a point that is guaranteed to be within a given polygon in PostGIS? I am aware of the ST_Centroid function. However, the centroid is not always within a polygon, see below: ...
17
votes
9answers
8k views

How can I convert an excel file with x, y columns to a shapefile?

How can I convert an excel file with x, y columns to a point shapefile? There are some somewhat optional requirements in addition to the correct creation of a shapefile: Column types (as per ...
10
votes
4answers
719 views

Point Pattern Analysis Algorithms

I'm looking for point pattern analysis algorithms and literature on point pattern analysis, online resources and book titles welcome. The topics may range from general descriptions of algorithms to ...