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

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3
votes
2answers
102 views

How to automatically draw lines with a given angle from one single point in qgis 1.8?

I'm new to qgis so please be patient. I need to draw a bundle of lines all originating from the same point and with a 10° angle between each line (e.g. lines bearing at 0,10,20 ..90..110..220..350). I ...
1
vote
2answers
142 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
2answers
184 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: ...
4
votes
1answer
211 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
1answer
58 views

How to find the polyline's ID connecting two points in ArcGIS 10.1?

I have an ArcMap (*.mxd) file with several layers including a point layer and a polyline layer. The points are connected by polylines in the polyline layer, and I wish to know how to list the ...
2
votes
1answer
118 views

Getting null values using Point sampling tool in QGIS 2.0.1

I would like to obtain the information of a raster layer at some points. Apparently the Point sampling tool does the job. I have used this tool, and all the raster values extracted at specific points ...
2
votes
1answer
613 views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
2
votes
1answer
263 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
1answer
121 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 ...
1
vote
1answer
43 views

Python script to select a point within a cell?

I have two features: points and grid cells (vector). I want to select a point within a grid cell (some cell do not have point) using python script and create a new feature layer with below conditions: ...
1
vote
1answer
56 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 ...
1
vote
1answer
77 views

What is the best way to display point data (with standard deviation) using QGIS/SAGA/Manifold?

I would like to display point data values (indicating biomass at a point) but also to show the standard deviation value for each point. What would be the best method to do this in QGIS (I'm a basic ...
1
vote
1answer
74 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 ...
1
vote
1answer
74 views

Counting points in a raster

Is there a way to select points in a raster dataset by raster classification? I have a floating point raster created from the points, classified into 4 ranges by standard deviation. I want to find out ...
0
votes
1answer
69 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 ...
0
votes
1answer
23 views

GRASS GIS v.in.ply

I'm trying to import a .ply file from MeshLab 1.33 into GRASS GIS 7.0 using v.in.ply addon, but I get the error message: ERROR: List index must be integer, is uchar This appears to be referring to ...
0
votes
1answer
47 views

Generating points from chainage and offset

I have a polyline layer and an external csv containing road sign data. The csv has unique ID of the polyline, chainage along each unique segment and an offset. I have access to ArcGIS, MapInfo and ...
0
votes
1answer
149 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 ...
-3
votes
1answer
127 views

How to create a polyline feature from a point layer

I would like to create a route line based on a point layer. The existing tool does not meet the customer requirement. But using the code snippet below, the start point and end point are always the ...
0
votes
0answers
24 views

Multiple Centroids within a dataset based on distance

Is there a way that we can find out the centroids of clusters within a dataset while differentiating one cluster from other based on distance not on any attribute value. The dataset is present in ...
0
votes
0answers
21 views

Can't get X coordinate of PointM in PostGIS

Here are two queries, and I can't understand how to filter points if st_x does not work in WHERE clause. select st_x(geom_merk), st_asewkt(geom_merk) from road_density limit 5; ...
0
votes
0answers
131 views

Polygon to point conversion in ArcMap

I tried to convert polygons to point using Feature to Point under data management toolbox in arcGIS 10.2 (got it from uni. licensed). I got the point layer but it is not showing anything. I added X ...
0
votes
0answers
68 views

Point features disappear when moved using QGIS 2.0

When I move, either by the node or the move function, a feature symbol on the map canvas, it simply disappears, not just the label, the whole thing. CTRL-Z brings it back. I'm using a MAC OS-X. I've ...
0
votes
0answers
145 views

Create a buffer area for a point c#

I am wondering to create a point/line based buffer zones in order to enhance my understanding for buffer concept in the GIS. The buffer zones can be any circle or region around a point, particularly, ...
0
votes
0answers
88 views

Building real-time point/polyline connection in GIS

In the first instance I need to create the network by constructing the basic elements, the nodes and links. This is relatively easy work as SharpMap has provided geometry tools that allow users to ...
0
votes
0answers
80 views

Arcgis custom spatialreference and geolocation problem

I have a tiled map service layer that has custom spatial reference. This is url of map. Spatial Reference: ...
0
votes
0answers
39 views

grass plugin in QGIS all of sudden not working as expected

The previous week I was able to use the grass scripts in the QGIS 2.0.1 Dufour toolbox, but today they do not seem to be working. I am not sure where to place a '-c' which was a solution to the same ...
0
votes
0answers
37 views

What is the easiest way to get points Info from OSM

I need to parse some OSM XML data to get some nodes with their tags. Does a program or script already exist to do this? The result can be any format that I can parse to DB, e.g. XML, CSV, txt file ...
0
votes
0answers
105 views

Create shape file with point

I am trying to create a .shp file with Point shapes. I am following this tutorial: http://docs.geotools.org/latest/userguide/tutorial/feature/csv2shp.html I create the project, no syntax error and ...
0
votes
0answers
32 views

How to split a feature using GDAL

I want a feature to be cut into 2 or more based on deviation of a segment i.e., the angle between 2 successive segments. At places, I may also require to merge 2 or more features.
0
votes
0answers
55 views

Uploading transmission line shapefile into spatialite.

I merged around 70 different transmission lines shapefiles of a state into one. Then, with a grid I divided the state into many features and got the centroids in QGIS. I'm trying to calculate in ...
0
votes
0answers
83 views

How to convert a set of points to a polygon based on a specific field in QGIS

I am having a point shapefile that consists of a number of point sets. I need to convert these points to a polygon based on a particular field in attribute table say for example locality . How can i ...
0
votes
0answers
301 views

Bearing Distance to Line tool from dBASE table only draws one line in ArcGIS 10

I am using the Bearing Distance To Line tool to draw geodesic lines to points defined by a bearing and distance. This is an aside, but I will then use the Feature Vertices To Points tool to convert ...
0
votes
0answers
147 views

Splitting a TAB file by attribute?

I have TAB file with LOADS of points. Each point as a unique ID and group assigned to it (ranging from 1-154). I'm wondering if there is an easy way to split this up into a TAB file for each group, ...
0
votes
0answers
55 views

How to format spreadsheet to input point data for later import to PostgreSQL

I want to create a spreadsheet to hold data from our cemetery. I will use the spreadsheet to get the data into a PostgreSQL database. What I dont know yet is the format that the point (positional) ...
0
votes
0answers
432 views

How to do a spatial join if QGIS 1.8 keeps crashing?

I am trying to perform a simple spatial join (adding polygon data to points) in QGIS 1.8: target vector: points join vector: polygons take attributes of first located feature keep all records ...