1
vote
0answers
13 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 ...
-1
votes
0answers
18 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...
3
votes
1answer
53 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 ...
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 ...
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 ...
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: ...
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
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") ...
2
votes
0answers
35 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 simply ...
1
vote
1answer
82 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
54 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 ...
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. ...
0
votes
0answers
36 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
0answers
32 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
89 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
77 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
52 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 ...
3
votes
2answers
189 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 ...
3
votes
0answers
62 views

Is there a “Disperse Markers” tool for QGIS?

I am using ArcGIS, but either I would like to use QGIS and maybe want to switch completely later. A have a point overlapping problem, as a result of geocoding of addresses. I have not found any ...
0
votes
0answers
77 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 ...
0
votes
1answer
76 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
0answers
21 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 ...
2
votes
2answers
89 views

How to convert a point layer to a raster grid that shows the frequency of points per cell in QGIS

I have a point layer that shows the distribution of a species. Is it possible in QGIS to convert this point layer to a raster grid in which the value of each cell corresponds with the amount of points ...
1
vote
1answer
40 views

QGIS hides few graduated points after reopening project

I have a strange problem in QGIS 2.2 (problem is also present in QGIS 2.1). When I add a point (shapefile) layer, apply graduated style and change point size, everything looks fine. Then I save ...
1
vote
1answer
242 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 ...
0
votes
0answers
44 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 ...
1
vote
2answers
43 views

Creating Many Uneven Buffers

Qgis 2.2, Windows 7 I am looking to create buffers around city lights (the raster). Currently, I have simple polygon buffers around the point layer (oecdminusa), but this is not accurately capturing ...
2
votes
1answer
55 views

Identify geographic location to points

I am quite new in QGIS and I really need your help. I have a map of Kenya divided into 68 districts and I have coordinates of 30.000 schools. The points have one variable besides the latitude and ...
2
votes
1answer
430 views

Problem creating point shapefiles programmatically using python in QGIS 2.2

I am trying to create a point shapefile in the memory buffer (for a temporary label) and then zoom to the extents on this buffer. The working (in version 2.1) test code for this is: def ...
2
votes
3answers
238 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 ...
3
votes
2answers
259 views

Line start and end nodes: determining what is a junction

I have a layer of points and polylines and want to determine which points are road junctions. I currently have all start and end nodes within 3m of my road network as a layer. However I cannot ...
2
votes
0answers
44 views

What is an Orphan point?

MY apologizes about the next doubt, but I can't understand what is an orphan point. I am using QGIS with a module to apply the Linear Reference System (the module is called "LRS"). During the ...
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 ...
1
vote
0answers
30 views

Creating contours from partial data set

Is it possible to create contour lines based on part of the points and not the entire dataset?
3
votes
1answer
126 views

How to horizontally align irregularly shaped point symbol to vector layer in QGIS?

Fairly new to QGIS and searching a method to graphically align my point symbols in the direction of the vector. The symbol represents a water valve in an irregular shape in close proximity to a vector ...
0
votes
1answer
81 views

Can I “undo” buffering of a point layer in QGIS?

I have point layer, where each point is one tree, about 1300 trees in total. I made buffers around each tree, the buffer being the height of each tree in QGIS 2.0.1. My next step was to use Spatial ...
1
vote
2answers
269 views

TIFF/Raster to Point shapefile question

Apologies in advance if this question is incredibly basic, but I've been googling around and I just don't know where to start. I've downloaded some nighttime luminosity data from NASA, and the data ...
0
votes
0answers
79 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 ...
5
votes
3answers
301 views

How to visually sort the order of Points with QGIS, GDAL, …?

The following Points layer is the basis of a rendering in a Android application. Android allows to draw a shape from the provided points. I cannot use LineStrings. However, the order of points ...
1
vote
1answer
100 views

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

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
104 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 ...
2
votes
1answer
33 views

Get coodinates from point shapefile

I converted a line shapefile to points as you can see in the attached image. Is there a way to know the coordinates of each point? Any help would be really appreciated! PD Im using QGIS 1.8.0
0
votes
1answer
160 views

How to display coordinates of a point in a projected cooridante system?

I want to check the coordinates of a point. On selecting this point in ArcGIS it displays a latitude and Longitude . In ArcGIS I found an option in 'Identity Tool' that the Latitude and Longitude ...
1
vote
0answers
57 views

How to auto-fill a new point vector in a vector layer?

When I work in-situ I manually add points in my shape-file. I would like that when I add a new point some attributes would already filled with values calculated programmatically. E.g in my first ...
0
votes
1answer
60 views

QGIS proximity raster with extent beyond original coverage?

I need a raster coverage of distances from points outside the geographic region of interest, and am having trouble doing this with QGIS. Questions like this one (Calculating distance to points in ...
1
vote
0answers
30 views

QGIS rule-based point style responding to number of co-located objects?

I am mapping the geolocated location information for 5.5k Twitter profiles as point data. Many of them have the same location ie "London, UK" meaning that they return identical coordinates. On the map ...
2
votes
1answer
201 views

Moving a shapefile point to specific coordinates

In QGIS is there a simple way to move a shapefile point in a shapefile point file to specific coordinates? Without exporting the points to WKT changing the x,y values and then importing the WKT via ...
0
votes
0answers
24 views

How to divide my area into adjecent polygons containing 80 points each? [duplicate]

I have a couple of thousand points in my dataset. I need to create clusters that each consists of 80 points. The specific selection of which points to put into a cluster is not critical - only the ...
1
vote
1answer
70 views

why are my buffers not lining up with their original points despite setting the layer crs as all the same crs when I reopen my project [closed]

I am having my entire project in pseduo mercator (google earth raster image) and when I create buffers for points and then open back up my project all the buffers are offset from their points. ...
7
votes
2answers
1k views

How to remove small “salt & pepper” polygons from a layer?

I have a map made up of multiple polygons, with a few hundred thousand points very small polygons on within it. I need the larger polygons, but not the points small polygons. How do I select and ...