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

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5
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96 views

How to connect centroids of lines sharing the same intersection in QGIS?

I'm looking for a big help to accomplish the following task: I have this street network of the center of Turin (IT), composed by lines representing streets, and black points representing ...
5
votes
1answer
295 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 ...
3
votes
1answer
135 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 ...
2
votes
1answer
37 views

Is there a better way to convert Raster to Point data? Don't need one point for every cell

I need to convert raster data to point data so I can use the points for interpolation via kriging. My problem is that my resolution is 5 ft and I'm working on a whole city. The data I am converting ...
2
votes
1answer
89 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
270 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
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1answer
353 views

How to obtain closest point of point over polylines layer in PostGIS 1.4 (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 ...
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1answer
37 views

Reduce number of points, keeping most recent data within a given distance

I have a HUGE dataset of points that were collected along a route. The data may change daily, and the most recent data is the most important. What I would like to do is take only 1 point from a given ...
1
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1answer
81 views

How to generate random points with minimum distances between points in multiple polygons

I am looking to create random points for a random stratified survey. There are three different categories being surveyed; for each, I have a single shapefile, each containing a number of polygons. I ...
1
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1answer
18 views

Join nearest points from 3 differentfeatures in ArcGIS 10.2

I have 3 point features. This points represent middle of tree trunks with attribute of diameter. The reason I have 3 features is that I used 3 algorithms how to calculate diameter. Now I need to join ...
1
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1answer
63 views

Select points with lowest elevations and same x,y coordinates

The problem is as following, I have a point layer with x,y,z coordinates. Some of the points have same x,y but different z. I need to separate points without duplicates (x,y) and in case there are ...
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1answer
50 views

QGIS 2.4: copying of points to another point layer

in QGIS 2.4 it is not possible any more to copy points of a layer into another layer - I get the message: " Fehler: Objektschreibfehler: Objekterzeugungsfehler (OGR-Fehler: Attempt to write non-point ...
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1answer
70 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: ...
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1answer
85 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
14 views

Add point button missing from CartoDB?

I'm trying to add a point to a map that already has points (table imported from a public source). However I do not have the 'button' on the right hand side in my 'map view' to be able to add in my ...
0
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1answer
34 views

CartoDB: How to I cluster by features? Is it even possible?

I have a set of points for a number of buildings in NYC. I would like to group those points into clusters per their respective neighborhood (ex: Chelsea, Upper East Side etc.). Each of my points have ...
0
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1answer
39 views

Create polygons from point dataset, where each polygon contains 3 points from the dataset

I'm using qgis Brighton I have a dataset of 1500 points. I want to create polygons, where each polygon contains n=3 points from the dataset. The aim of this is to have clusters of 3 points, which ...
0
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1answer
27 views

Accessibility indication from points

I will simplify my question to be better understood. Let's suppose my study area is consisted by settlements A and B. They both have the same population (1000 people each). Each settlement was ...
0
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1answer
57 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 ...
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0answers
14 views

Difficulty creating a point layer using the line intersections function in QGIS

I am attempting to create a point layer from two line layers where the lines cross. I am using QGIS's built-in Line Intersection tool but the output point file created remains empty. I have checked ...
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0answers
10 views

Creating a point in a fixed distance and course

How can I create a point in a fixed distance and course from an existing point using the Microsoft SQL SqlGeography object ?
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27 views

Point to Raster Converting Result

I had a problem with Point to Raster converting result. I had an Excel file which contains x, y and z values. I wanted to create an individual raster data from classified z values so I planned to use ...
0
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0answers
55 views

What's the best way to convert points to raster and back again?

To convert raster grids to vector points In QGIS there we have different possibilities (grass tool "to.vect"; saga tools "grid values to points"). My problem is a little bit complicated. In the ...
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0answers
28 views

How to map data from USGS NAS database, using HUC?

I am querying the USGS NAS (Nonindigenous Aquatic Species) database. The collection data for the results that are returned don't include lat/long points, but have an HUC (Hydrologic Unit Code). I have ...
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34 views

Parameters for CreateFishnet

I´m about to create a fishnet. The CreateFishnet tool has several parameters, between them the origin_coord - The starting pivot point of the fishnetl. Data type of this parameter is Point Now there ...
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12 views

Pavement survey implementation

I know I am supposed to be specific...BUT I am working as part of a research team on pavement study. I need to visually display survey data in Arcmap. The surveys consist of x transverse ...
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65 views

How to convert geometric point to geographic point in SQL Server?

I am new to sql geometric and geographic types What I need is a way to convert a sql table of geometric points into geographic points?
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53 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: ...
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41 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 ...
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42 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 ...
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0answers
84 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 ...
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80 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 ...
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263 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 ...
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72 views

Use python to execute GRASS module v.distance

I have successfully use python script to import a line shapefile and a point shapefile into GRASS, and the following are their attribute table in QGIS, line shapefile point shapefile Now I want ...
0
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0answers
127 views

PyQgis: How can I “append” features to a Vector Layer instead of “stacking” them?

As I read data from a text file and add points to a QgsVectorLayer (as well as related attributes), each new record gets 'stacked' on top of the previous one in the Attribute Table (and within the ...
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0answers
14 views

Where are the settings that control when clustering starts and stops?

We have a SDE set up on a SQL Server and we're using the Silverlight API. Our layer has buildings on it. The flare clustering and large clusters show when the map is opened and the actual buildings ...
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33 views

Statistics on matching point layers ignoring nodata values in QGIS

I have a large area and a street crossing this area. Both are vector point layers in QGIS. The large area contains -99 as NoData value. I already created the intersection of both as a new layer. I ...
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53 views

Split polygon into four with respect to single point

Some days ago one of my colleague came to ask me a query related to Geometries. The situation is as....There is one Polygon(suppose a city polygon) and there is one point(suppose user's current ...
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56 views

Reducing point numbers in a certain area

We have a list of poi data in our database(Access mdb db), and we have a web service which serve data by a specified BoundingBox. However we found that the returned points are too close to another at ...
0
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85 views

Pointstack with different count-1-symbols / SLD / GeoServer

I try to use the pointstack sld to visualize my data at different scales. I used the example from http://suite.opengeo.org/opengeo-docs/cartography/rt/pointstacker.html, and everything is fine. ...
0
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0answers
45 views

How to create a point representing a polyline?

How do I convert a line (usually 2 vertices but can be more) into a single point in QGIS? I did it a couple of years ago using a build-in tool in ArcGIS 8 or 9 I think but have no idea how to do it in ...
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21 views

Point in Linefeature build through specific topology rules

i want to build Lines from Point Features following different topology rules (that lines aren't like randomly build, but how i should be following the extent from other polygons for example.. when ...
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0answers
93 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 ...
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133 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 ...
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0answers
130 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 ...
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104 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 ...
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438 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 ...
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224 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, ...
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57 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) ...
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0answers
462 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 ...