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

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2
votes
1answer
294 views

Postgis 1.4 - Obtain closest point of point over polylines layer (without st_ClosestPoint)

I´ve got a polylines layer (pipes) and a points layer (valves) and In Postgis 1.4 I would like to obtain the closest points but exactly on the closest polyline. In other words, i need to locate each ...
1
vote
0answers
12 views

QGIS PointConnector Plugin - x out of x lines not drawn

Unfortunately every try to generate lines between points (.shp) with ids (1-6) and a csv-file with from - to values failed. Maybe you can give me a hint whats wrong with my workflow? 1) I generated a ...
2
votes
0answers
25 views

Geoprocessing tool for finding specific point within polygon

I have a ArcGIS task and cannot find a solution. I try to find a certain point within a polygon (see picture). This example is handmade and I need a geoprocessing solution I point I try to get is ...
5
votes
1answer
239 views

QGis 1.8 fails to rotate point geometries with rule-based style

I have to do some visualizations in QGIS (1.8.0) and up to now I've been very happy with the new Dialog "Layer Properties -> Style", using the rotation-field to rotate Point-Geometries visualized by a ...
2
votes
3answers
236 views

Draw line between points from multiple datasets

I have 2 point datasets and want a tool or script to draw a line between all points in one dataset to all the points in the 2nd dataset. Is it possible? I have tried ESRI "Point Distance" and ...
0
votes
1answer
42 views

How to Calculate the average value near a point

I am new to ArcGIS ArcMap. I want to calculate the average value of one point ( layer flowline ). This could be done using the value of the point and the values of the four neighbor points ( raster ), ...
-1
votes
0answers
17 views

how to move point(points) by a vector in Qgis [closed]

Can anybody help me with the problem of moving the point by a vector in Qgis. I have no idea how to do that...
2
votes
1answer
53 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
49 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 ...
0
votes
2answers
181 views

How to extend polylines to the nearest point

Hi could anyone tell me a way of getting my polylines to search for a point within a certain number of meters of their start/end points and extend to it? edit: There was some broblem uploading a ...
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 ...
3
votes
1answer
89 views

How to map flood areas from a set of points containing surface and height of water?

I am working on the damages made by the typhoon Haiyan. I use QGIS 2.0 with extensions and toolbox, and MapInfo. I have vectors, rasters of the place. I want to map the flood area along the ...
3
votes
1answer
52 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
59 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 ...
1
vote
0answers
20 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 ...
1
vote
1answer
103 views

QGIS how to compute a trendline of two point lines?

Does anyone know how to compute a trendline for two lines of points? I have two lines of points of a 10 km long urban road. 1st line is one driving direction and the 2nd line of points ist the other ...
3
votes
2answers
2k views

Update point coordinates in QGIS after manually moving locations in edit mode

I have imported point coordinates from a database, but I need to manually adjust a lot of the locations. Is there a way for QGIS to automatically update the point locations in the attribute table ...
7
votes
4answers
1k views

How to create different diameter circles round points?

I want to map a tree survey. I am thinking that I will plot positional points of the trees and then add other data like tree type etc. to the attribute table later. Is there a way I can have an ...
0
votes
2answers
228 views

Create multi-line from point in PostGIS

I'm working on an old table where polygons are stored as points. Now, I want to migrate these points to PostGIS and store them as polygons (or multi-polygons). The table structure is as follows: ...
0
votes
2answers
56 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 ...
6
votes
2answers
2k views

QGIS calculate distance of point along a line

I have a polyline (movement path) and points recorded along the line. I would like to calculate for each point the distance along the line in Quantum GIS. I hope for a result which will add a new ...
0
votes
0answers
22 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: ...
2
votes
2answers
323 views

How to find the nearest single point?

I have two shapefiles containing each one set of points, set A and set B. One set is my random selection (set A), the other is a list of communities (set B). For each point of the random selection ...
2
votes
1answer
61 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 ...
3
votes
4answers
1k views

Calculate min distance between points in PostGIS

I have point layer in PostGIS database. Help please with query which add for each points in layer distance in attribute table between this point and another nearest point. Thanks! Update Calculate ...
1
vote
1answer
41 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 ...
2
votes
0answers
45 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 ...
6
votes
3answers
933 views

Adding “noise” to overlapping X,Y coordinates so no longer in EXACT same place?

I have a series of points representing animal observations. Many of them overlap, having the exact same coordinates, and this is causing me trouble when I want to run some analytical tools which ...
5
votes
6answers
4k views

How to represent several points with same coordinates on map? [duplicate]

I'm working on Arcgis 10. I have a point shapefile representing events with several points having coinciding coordinates (They have the same coordinates). For representing them in a dynamic way, I ...
1
vote
0answers
26 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 ...
0
votes
1answer
173 views

Get points along a polyline at defined distance c#

I need to store into my array the points along the polyline at each defined distance. Example: The Polyline length is 50m, I set the interval to 5m. I have to store in the array all the points along ...
1
vote
1answer
241 views

Split a line feature using nearby points

I have a line shapefile and a point shapefile, and the line has its own segments and its attribute table, the point shapefile has points near the line above, not on it and the close ...
3
votes
3answers
605 views

Performing join on simultaneous spatial and attribute criteria in ArcGIS for Desktop?

I have two point layers and want to perform a spatial join on nearest distance. Normally it is easy with ArcMap. But now I have a restricting condition on the spatial join. The restriction only ...
5
votes
3answers
172 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 ...
3
votes
2answers
63 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.
1
vote
1answer
38 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 ...
1
vote
2answers
79 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 ...
2
votes
1answer
4k views

Making POINT from longitude/latitude coordinates in existing table using PostGIS?

I would like to make a POINT using the longitude and latitude columns of an existing table. Here's a link to the documentation of ST_MakePoint. Here's my table: CREATE TABLE sysinst.bio ( oid ...
1
vote
0answers
81 views

Spatially join points to polygons in arcGIS

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 ...
2
votes
1answer
44 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
40 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 ...
2
votes
1answer
138 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
0answers
114 views

Can't zoom to feature from Datagrid with ArcGIS API for JavaScript

I have a find task in my application that returns features that are points, lines and polygons. I can get the search to populate the datagrid but I am having problems with my onRowClickHandler ...
0
votes
1answer
17 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
29 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") ...
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
0answers
58 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. ...
2
votes
1answer
28 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
64 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
24 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 ...