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

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5
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0answers
100 views

Point sampling along a pole-wrapping coastline with PostGIS

I am working on a task that requires me to get sample points every 1000KM along coastlines, and have run into a problem with Antarctica. From what I can tell, it seems to be an issue with the use of ...
1
vote
0answers
28 views

Routing and OpenLayers: How would you connect a point to another through a 'road' node? [duplicate]

So my question is in a routing application,probably using osm as base layer, how do I get a line-string that goes through the road and not directly from one point to another? Is there any ...
1
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2answers
698 views

Avoiding R for windows gui front-end has stopped working error?

I am trying to load huge number of points (shape file) in R. But when I load it, the program displays following error message and just stops. "R for Windows GUI front-end has stopped working" My OS ...
1
vote
0answers
96 views

Spatially join points to polygons in ArcGIS Desktop? [duplicate]

I am trying to join a point feature class to a gridded polygon feature class in arcGIS so that all the points are matched to the grid cell that they fall within. I would like to end up with an ...
1
vote
1answer
46 views

How to find ID's of nearest stations (points) in a specific radius

I am using ArcGIS 10.0 and I am doing rainfall data analysis. I have a single layer including more than 1,000 stations (points) and I need name (STATION_NO) of neighbor stations in more than one ...
3
votes
1answer
238 views

Performing Point Distance analysis using Basic level license of ArcGIS for Desktop?

I am using ArcView Version 10.1 and I need to perform a point distance analysis like: What is the distance from A to B-Z, B to A-Z, C to A-Z, etc? What are the steps that I take to do this?
1
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0answers
52 views

Using Geoserver

I am new to GIS and interested in using Geoserver. I have had a look at tutorials and read some books on this but still feeling clueless. I intend to use C# to accomplish some tasks eg, plot points on ...
3
votes
2answers
89 views

Analysis of lines in a point in QGIS

I have 33 layers, 1 with points and 32 with lines. I want to extract/highlight the points where more than one line is intersecting. I have tried with buffers but I'm not getting anywhere.
2
votes
1answer
606 views

Converting set of points to polygon using C#?

I want to convert a set of gps ponints to polygon.I used a simple loop to convert it to a WKT and than used makevalid() in sql server and save it in a gemetry column in databasae.Is this way right?or ...
0
votes
1answer
41 views

How to convert 3d profiles to points in ArcGIS 10.1

I have created some 3d profiles using the Interpolate Line button (in ArcGIS 10.1). Which looks like: I would like to convert these lines into points and in order to do that I am under the ...
1
vote
1answer
37 views

Point input for polyline not acceptable?

Input QgsPoint(s) are returning an error in a Polyline creation routine. Any clues?! processing.runandload("qgis:polygoncentroids", Base, "memory:CenterNode") ...
6
votes
2answers
404 views

Normalizing point cloud data

How I can get Digital Height Model (only object heights, DSM - DTM = DHM)? Many applications can do this, but they convert it to GRID or TIN format. I was wondering if it was possible to keep the ...
2
votes
1answer
33 views

finding the nearest point outside a series of geometries

I have db with a very large amount of geometries (circles), most of them overlapping. I'm trying to come up with a way to find the nearest point (from your current location) that is not within any of ...
1
vote
0answers
176 views

OpenLayers - Add points at vertices of line while drawing line

I would like to create points while I draw a line on my map in OpenLayers. That is, at each vertices of a line and at the end points there is a shape like a square, circle, or diamond. I have this ...
3
votes
1answer
58 views

Deriving coordinates from Application.Display or MxDocument.ActiveView in ArcObjects?

I've found two possible ways of converting a MouseEventsArg's coordinates to the coordinates of the current map: The first is taken from a snippet included with ArcObjects: protected override IPoint ...
2
votes
0answers
74 views

How to Interpolate very large datasets in QGIS?

I am working with a very large set of point data, (XYAttribute) which I wish to display as a raster. I've been using Interpolate, this is successful but very slow. I have other programmes that ...
3
votes
1answer
268 views

Find the closest line vertex from the linestring using PostGIS

How to find the closest line vertex from a linestring? ST_ClosestPoint will give a point which is not from the linestring.
2
votes
1answer
172 views

QGIS 2.4 Layout View pdf/raster file export moves points

I created a map, using a google basemap (openlayer plugin) and imported a table as a csv file (containing a name of a city, latitude, longitude for wgs84 and a row named "amount"). It displays ...
2
votes
1answer
192 views

Delete duplicate polygon nodes with PostGIS

I'm trying to delete duplicate nodes from a shapefile with QGIS, but after running the tool to delete it, nothing happens and shows the same errors. I thought that maybe importing to postgis could be ...
1
vote
1answer
58 views

ValueError when instantiating LineString from a mix of tuples and Point objects

I'm new to Shapely, and tried instantiating a LineString object from a mix of tuples and Point objects like this: >>> LineString([Point(1,2),(2,3),Point(3,4),(5,5)]) I get the following ...
1
vote
1answer
97 views

WKT: What is the reasoning behind the concept of a POINT EMPTY?

In data formats like WKT and WKB, we have ways of representing "empty" geometries. That all pretty much makes sense: a "LINESTRING EMPTY" is a LINESTRING type with 0 vertices. Same with a MULTIPOINT, ...
3
votes
2answers
74 views

How to automate drawing a polyline from 2 intersecting datasets based on proximity?

I've been stuck on a situation recently where my company's data has to be integrated with another. Basically there are two point shapefiles comprising of >50000 points, and as shown in the image ...
1
vote
1answer
46 views

Creating random location within a network from a given location and a given distance

For a habitat selection study, I am trying to identify availability. My species lives along waterbodies and I could assess distances moved between two consecutive locations using the network analyst ...
0
votes
1answer
518 views

The best way to convert points to polygons using ArcObjects

I have a set of points from GPS I want to convert them to polygons..I have two approaches to do this.1- convert points to polygon..I do this with below code: private IPolygon ...
1
vote
2answers
1k views

Creating density map from point data?

I have point data, where one point represents one 1 storm water outfall, looks like this: (point data is across all of Long Island, New York). I am having a bit of difficulty finding the best tool ...
5
votes
0answers
205 views

How to compare two sets of points in QGIS?

I have two point layers with XYZ data; one set are points measured in the field and the second set is a Lidar data set. I want to check the accuracy of the Lidar in comparison to the measured data. ...
0
votes
0answers
43 views

Reading Points as PolyLines

I'm currently developing an Android app where I need to show some information on a map, which is stored as Shapefiles (.shp + .shx + .dbf). I noticed that when the shapefile is opened in QGis, a nice ...
0
votes
1answer
126 views

TIN file to a POINT file

I have some bathymetry data in TIN format; I am able to open this in arcmap and view the terrain. However I need to use this data within a simulation framework called Delft3D, which needs the ...
0
votes
0answers
56 views

QGIS Rasterization of points

I have a point vector layer and want to make it a raster. Trouble is that many points are very close to each other, so unless I specify a very small resolution of the raster cells, likely several ...
3
votes
1answer
194 views

Calculate distance between point and linestring and how to represent that on QGIS?

I have loaded my data with osm2pgrouting and I have my network with ways (Linestring) and nodes (Point). The problem is : I have a database of doctors addresses (point) and I should calculate the ...
2
votes
2answers
119 views

QGIS polygon centriods - How are they created?

I have been using QGIS to analyses spatial data and I created polygon centroids with the vector geometry tools. Now for a report I have to explain how these centroids were created. I have not been ...
0
votes
0answers
99 views

how to remove a point or polygon in shapely python

I want to place minimum number of sensors(circles) to cover a maximum area(polygon). I am using "Shapely",python module. I want to know if a sensor i.e a point buffer inside the range of the other ...
0
votes
2answers
196 views

Adding end nodes to a line

I'm hoping someone can help me here. I have a line feature and what I am trying to achieve is to determine is in which direction the line ends. I understand that this could be achieved with ...
1
vote
1answer
435 views

Iterating over all features in featureclass to intersect them individually with polygon using ArcPy?

I've got a point featureclass, and I'm trying to individually intersect each feature with a polygon featureclass to get some information about which polygon each feature is in. I did one intersect ...
1
vote
1answer
185 views

Intersection of two polyline geometries not returning expected coordinates?

T2B = arcpy.Array([arcpy.Point(1,2),arcpy.Point(-1, -2)]) L2R = arcpy.Array([arcpy.Point(0, 2), arcpy.Point(1, -2)]) L2R_line = arcpy.Polyline(L2R) T2B_line = arcpy.Polyline(T2B) cent = ...
2
votes
4answers
149 views

How to set a minimum point snap distance?

There are two points: A and B. I need to snap any points within a 65 m search radius (blue buffer) of point A. However, the snap distance of B needs to be exactly 5m apart from A (i.e. located ...
5
votes
0answers
80 views

Point to point and point to line [closed]

I have several points. These points are far from some lines. I want to make the following: If two points are closer to each other than the maximum distance of one of these points to the closest ...
0
votes
0answers
87 views

Can I create a cross section from points along a line without using a DEM in QGIS?

I have a set of points perpendicular to a river and would like to present a cross section of them. Like a simple graph in Excell for example, with Z as y axis and distance along the line as the x ...
0
votes
1answer
192 views

Density analysis producing extreme values?

I have point data of gas flares and I am trying to create a simple density raster of those flares. Results are either 0 or in the 100,000-1,000,000 range (when there's 5 to 40 or so points in each ...
2
votes
1answer
165 views

Buffers with Varying Distances around a Set of Points

I have set of points in one shapefile and I have a table with a unique identifier that matches each point. I want to make a buffer around each point, according to the radius that I have specified in ...
0
votes
1answer
105 views

converting random point order into polygons

We received a kml file with polygons but the points are not in a logical sequence and we end up with strange overlapping shapes that are supposed to be an open polygon. We did identify a point near ...
0
votes
1answer
341 views

How to calculate point from lat/long, angle, and distance? [duplicate]

I am trying to calculate the point from a given lat/long, a bearing, and a distance. This is for plotting weather given a aeronautical way point. For example: Given a waypoint with a known ...
1
vote
2answers
349 views

Calculating distances between points two feature datasets

I will do my best to explain my problem. I have two feature datasets. One set has about 100 points that are "city centers." The other dataset has points for each census tract in each of these 100 ...
1
vote
1answer
165 views

Export a large raster to a comma or tab delimited text file in ArcGIS 10.2 for Desktop

I have a large raster with multiple attributes in 200-meter cells, and I would like to export this to a tab or comma delimited file which contains the X,Y coordinates and all of the attributes. If ...
4
votes
1answer
692 views

How do you hide a feature within a point layer?

I know this is basic, but for the life of me I can not remember how to hide/disable a specific feature point within a point layer. This seems like it should be a 2-3 click solution, but working with ...
2
votes
1answer
106 views

Spike finder in PostGIS

I tried to modify spikeRemover from Schmidt & Krüger. My goal it's to obtain, for each polygon, the position of the spikes. I don't need to remove it. For some reason, that I can't figure out, my ...
2
votes
2answers
742 views

Change points to polygon

I have a map which has one data point per zip code. I would like to change those points to zip code polygons. Any ideas on how to go about it?
1
vote
2answers
558 views

Get points, along a polyline, at defined distance

I need to store into an array the points, along a polyline, at each defined distance. Example: A polyline length is 50m, I set the interval to 5m. I have to store in the array all the points along ...
2
votes
0answers
39 views

Extracting outtermost points from a irregular grid of points

Good day to all, I am using Arcmap 9.3, and would like to remove all points inside an irregularly placed grid, except the outermost (boundary) points. For example, I would like to keep the black ...
3
votes
1answer
257 views

Project point to map with Arcpy using GPS Coordinates

I am trying to create a new layer with just a single point using arcpy. All that is provided is a gps lat and long. It seems like it should be a simple problem but I just can't get it to work. I've ...