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

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3
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1answer
180 views

How can I create an DEM from Point-Data

my boss gave me a small 3D-point-shape-file and asked me to make an DEM from it, wich I should put together with an older DEM of the same site, wich was made with Surfer. I created a raster-layer from ...
3
votes
1answer
151 views

How to find mean coordinates of a cluster of points from a point layer in QGIS?

I have a set of coordinate points. The points are distributed in such a way that some points are clustered around a specific area. There is an option to find out mean coordinates(s) of the whole point ...
4
votes
1answer
184 views

Creating a point corresponding to the maximum elevation of a DEM [duplicate]

I am wondering how can I create a point corresponding to the maximum elevation value of a DEM. I mean, from the DEM I can easily get the maximum elevation. For the sake of a viewshed analysis, I would ...
3
votes
1answer
168 views

QGIS - Calculate distance between a point layer to n nearest polylines

In QGIS I am trying to calculate the distance from a point layer to a polyline layer for the n nearest polylines. I have figured out how to calculate this distance to the centroid of the polylines ...
1
vote
0answers
29 views

How to get attributes from line-polygon where points are snapped on, into the point-layer?

I have a SQL Server spatial table with point-objects, the points are set by snapping onto a line SQL Server spatial table. so the points are georeferenced on the line. How can I get the attributes ...
0
votes
2answers
128 views

Curved Arrows showing trade ARCGIS 10.2 [duplicate]

I have 10 points that represent the centres of countries. I want to show with arrows the flow (some kind of trade) from one country to another. The way that my table of attributes is constructed is ...
0
votes
0answers
62 views

export qgis point symbols per feature

I am currently trying to export the drawn symbol in a QGIS map for a webmap. The current approach is to extract the properties: if i.rendererV2().dump()[0:6] == 'SINGLE' and i.geometryType() == 0: ...
3
votes
1answer
296 views

ArcMap - Display direction of points

I imported a few geotagged images and created a points shape showing their locations (or more accurately, the location of the camera) with the "Geotagged Photos to Points" tools. The attribute table ...
1
vote
1answer
65 views

Looking for information on methods or algorithms used to calculate centroid from polygons across software

Looking for information on methods or algorithms used to calculate point centroids from polygons across software. ArcGIS uses a "gravity model" but can someone point me to the math or a paper on the ...
5
votes
0answers
84 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
27 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
vote
2answers
523 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
94 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
44 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
185 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
vote
0answers
50 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
86 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
435 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
34 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
36 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
331 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
147 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
48 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
55 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
213 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
150 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
155 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 ...
0
votes
1answer
44 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
72 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
67 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
42 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
344 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
759 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
161 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
42 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
97 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
49 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
162 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
110 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
85 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
158 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
351 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
163 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
139 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
75 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
82 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
160 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
159 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
92 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 ...