Questions tagged [point]
A geometric element defined by a pair of x,y coordinates.
2,338
questions
3
votes
2
answers
2k
views
Extending line by adding point at end of it using QGIS?
I'm using QGIS 2.8 to modify a line. I need to add a point on one end of this line, and then move this new point further away, leaving the original end point in the same place.
I can manage to create ...
0
votes
1
answer
324
views
Unable to insert geometry point using TypeScript and MassiveJS
I am trying to simply trying to validate a point before I actually insert it into the db.
I am using the following:
TypeScript: 3.5.2
MassiveJS: 6.4.0
PostgreSQL: 11
PostGIS: 2.5
const ...
7
votes
4
answers
5k
views
Getting the mean coordinates of point features in QGIS
I have a vector layer containing several points and I would like to generate the mean coordinates of these points, using QGIS only if possible. I'm looking for something similar to centroids, but for ...
1
vote
0
answers
46
views
Placing a point inside a convex polygon [closed]
I want to place a point inside a convex polygon. Is the position that maximizes the minimum angle of each triangle unique?
I'm not very familiar with computational geometry, but I feel like this ...
2
votes
2
answers
446
views
Export/convert Points to Polygon
I have to convert a .shp into a .csv file and upload it to the SQL Server, for a program that only supports Polygon format and can not render Points.
Is there a way to convert Points to Polygon or is ...
2
votes
3
answers
247
views
Styling polygons of postcode zones that contain a point (address)
I created a Map with Geocoded Addresses from the UK. The Basis for the map is a UK districts shapefile, this constitutes my main layer. After geocoding (via .csv) 3 Addresses I have a new layer with ...
7
votes
3
answers
487
views
Creating bar chart from point layer using QGIS Geometry Generator
From a layer with point geometry, I store the following fields:
"CATEG" which can be A or B
"ORDER" which is an autonumeric field sequence without repetitions
"VALUE" ...
4
votes
1
answer
78
views
Label placement with callouts in QGIS
If I create point data and label them with callouts, I have the following problems:
The callouts will cross each other
The Text is over the points
It seems quite messy
I want to automate this ...
0
votes
2
answers
243
views
QField edition: deplace point object
I would like tu use QField to update localisation of points objects that their fields are already informed.
With the editing tool I don't manage to deplace point despite I see several "how to&...
0
votes
2
answers
534
views
Converting points with Easting and Northing to polygons of GB OS Grid references?
Is there a tool or procedure on ArcMap 10.8 (similar to the Tom.bio plugin in QGIS) that allows the conversion of points with easting, northing and grid reference info into polygons of GB OS Grid ...
11
votes
2
answers
240
views
Creating buffers to closest distances with two categories in QGIS
I would like to develop an expression that does the following nearest-neighbour analysis:
From a layer of points 'point_layer', I would like to calculate for each point the distance to the nearest ...
5
votes
3
answers
1k
views
Determining on which side of line points are located using QGIS
I have a point shapefile (point.shp) and a line shapefile (line.shp). I want to determine on which side of the line each point is located.
The best would be to use a PyQGIS command to add a field to ...
14
votes
4
answers
26k
views
Removing duplicate point features using QGIS
I have created many .gpx data with my Garmin device, but due to the amount of data, I have imported the mapping data from my device several times (also because I didn't want it to be lost).
As a ...
3
votes
1
answer
290
views
Calculate distance from centroid to border of polygon
I'm trying to measure the overall distribution of parks in a certain part of the city. For this, I have already retrieved a layer that consists of the park-polygons, and created a layer of hexagons, ...
0
votes
0
answers
40
views
How to make raster from points in QGIS
I have these points and I want to make raster from this layer based on Dist2River attribute.
I used Rasterize
What should put for these to create a normal raster?
5
votes
2
answers
994
views
Select by expression and remove points
How do I select points by expression and delete these selected points?
Is it possible to do this inside the modeler with a tool?
The selection by expression works fine but do I have to set all the ...
2
votes
1
answer
163
views
Adding simple Geomasking (Donut masking) feature using PyQGIS
I would like to add a simple halo masking feature/plugin in QGIS. Halo/donut masking basically transforms (shifts) all points in a layer to a random distance between two user-provided distances. ...
4
votes
1
answer
404
views
Extract Max or Min Value from Point File Attribute and then Add XY Coordinate
I have created a Point dataset by using the Saga routine 'Convert Lines to Points'. This produces the following look and attribute table:
Can anyone advise on how I can extract the maximum value from ...
5
votes
3
answers
308
views
Labeling count points within dissolved buffers in QGIS
I am using the following expression to visualize with a buffer, the nearest neighbors at a given distance:
case when
distance(
$geometry,
array_get(
overlay_nearest(
layer:=@layer,
...
5
votes
3
answers
260
views
Symbolising point shapefile in QGIS: half blue half red colored point
I have a point shapefile. I have one point which I want in two colors. One half should be blue, the other one red. It should be divided vertically.
I tried the gradient version but it is as it says a ...
3
votes
1
answer
299
views
Create multiple callout lines from a single label
I would like to label groups of points (clusters) with only one label but several call-out lines. I built on top of the very appealing answer from @eurojam here: How do I give one label to two points?
...
2
votes
1
answer
255
views
Applying reverse QgsCoordinateTransform on QgsGeometry in PyQGIS
I have defined xform as a QgsCoordinateTransform to project geographic coordinates.
I can use:
unprojPoint = xform.transform(point, QgsCoordinateTransform.ReverseTransform)
to do the reverse ...
0
votes
0
answers
26
views
GeoServer CSS point attribute filter removing data but visible on layer
I am trying to create a point layer with the constraints as follows:
If [current year] - [year of data point] <= 3 then use square symbol otherwise use circle symbol
Regardless of the year of the ...
1
vote
2
answers
281
views
Creating an irregular point grid with provided row and column numbers in PostGIS
I am looking to create an irregular grid of points via PostGIS, using the four provided corner (point) coordinates, and number of point-rows, and point-columns.
Four corners may or may not be ...
1
vote
1
answer
2k
views
Adding and filling GEOMETRY column in new spatialite
I have three tables. One has no geometry. The second is POINT type, and shows up correctly on the map. The third is, for the moment, a simple checker table, don't worry about it.
I am able to perform ...
3
votes
0
answers
33
views
Error with St_geomfromtext in PostGIS [closed]
When I try to insert a point into a point layer, getting the coordinates with the following line:
select avg(st_x(the_geom)), avg(st_y(the_geom)) from centroide;
I get an error when I run the ...
1
vote
1
answer
683
views
Count number of points on a line in R
I have a SpatialLinesDataFrame and a SpatialPointsDataFrame. I want to calculate the number of points that fall on a line by a specific field in the lines data frame.
Example: I have a river network ...
15
votes
4
answers
12k
views
Creating perpendicular lines on line using QGIS
In QGIS I want to create perpendicular Lines on another Line (River). The Lines should be created on points on the Line and should have a length of 40 Meters. I want to create the red lines in the ...
3
votes
1
answer
135
views
Creating SVG point symbol depending on content of attribute field in QGIS
I have almost 300 localization of different airports with name by ICAO,
for example my column name is "ICAO" and values are "EPGD-Gdansk", "EPWA-Warsaw" "EPWM-Warsaw&...
2
votes
1
answer
69
views
Deleting points close to each other using QGIS (point thinning)
I'm trying to decimated a point shapefile to remove points close to each other.
If you look at the example below, you can see points are 30cm apart, but other are closer.
I just need to remove ...
2
votes
1
answer
39
views
Clustering points by number and accumulation
I'm recently working on a project, where I have a dataset of 450 Points. I need to cluster them into groups of maximum 80 and minimum 60 Points, which should also be located next to each other.
By ...
1
vote
1
answer
95
views
Using QGIS Model Designer to rotate points but it moves the points location
Using model designer to automate a process and I would like to be able to rotate points whether it be using the affine transformation tool or the rotate tool. I have gotten both of these tools to ...
0
votes
0
answers
19
views
What exactly is a grid point? I am trying interpret methods for replication
These methods describe how the researcher built a model training dataset for the purpose of wetland prediction using points as training samples. My goal is to understand how these points align with ...
0
votes
0
answers
25
views
How do I mirror image and rotate a layer of points in ArcGIS Pro?
I can't use the Rotate or Mirror tool since it's not a raster, and if I convert it to a group of rasters I lose the point labels. What can I do? Alternatively, is there a way to label a group of ...
0
votes
0
answers
19
views
Using QGIS, what is the simplest way to find the closest point in one layer for every point in the second layer?
In QGIS, I have two layers of points (layer #1 - blue, and layer #2 - pink).
How can I find the closest point in layer #1 for each point in layer #2, and then save this new selection as its own new ...
1
vote
1
answer
45
views
Generating points inside each polygon based on colorful raster layers data with QGIS
I have to automatically generate points inside each polygon based on colorful rasterlayers point density and/or color. Each polygon has to have 'X' number of points depending on its surface area, for ...
0
votes
2
answers
80
views
What are the QGIS words for my 4 types of data?
My project has 4 types of data:
a raster satellite view (Google Maps), to be the base layer and geolocated by three points (CSV) that apply to visible points on the raster map;
individual points: ...
0
votes
1
answer
585
views
Extract Points by Attribute for each Intersecting Polygon in ArcGIS Pro
I have a points shapefile and a polygon shapefile, each with millions of features. All points lie spatially within polygons so that there is one or more points within each polygon.
The points have an ...
3
votes
2
answers
3k
views
Creating path between many points in Google Earth
Is there any specific way to convert approximately 25000 points in Google Earth Pro to paths or draw paths between points automatically? Since I want to obtain their altitude data, I need it to be a ...
0
votes
0
answers
32
views
How to find a path that goes through all points of a 2d graph while alternating between X axis and Y axis
I know my title isn't very descriptive, i'll try to explain it better here.
Let's say I have a list of coordinates that is built as the following :
list = [ (0,0) , (1,0) , (0,1) , (1,1) , (2,0) ]
The ...
6
votes
1
answer
702
views
Azimuth calculations using PyQGIS
According to the QgsDistanceArea docs, an azimuth for computeSpheroidProject should be:
in radians, clockwise from North
So, to build a new point with computeSpheroidProject I use math.radians(...
16
votes
2
answers
4k
views
Difference between QgsPoint, QgsPointXY and QgsGeometry.fromPointXY() in PyQGIS
I am using PyQGIS. What is the difference between:
QgsGeometry.fromPointXY(QgsPointXY(x, y))
QgsPointXY(x, y)
QgsPoint(x, y)
When I print these three options, I get:
print(QgsGeometry.fromPointXY(...
3
votes
1
answer
85
views
Deleting duplicate points by attribute in shapefile using QGIS
I've got a point shapefile which has a single attribute (elevation Z) and there are a lot of duplicate points (several points in the same location but each one has a different Z value). I would like ...
2
votes
0
answers
21
views
Isolating points from a line shapefile (and check the attributes from specific points) using QGIS
I am new to QGIS and spatial data handling. I have a shapefile of a boat track and a shapefile of the border between two countries in QGIS. Parts of the boat tracks are in the waters from country 1 ...
1
vote
1
answer
560
views
Creating a Point with SRID - MariaDB
I have a table containing a longitude and latitude (as doubles) in MariaDB. What I'm trying to do is create a point with a specific SRID - 4326. The current way that I create a point is by using the ...
2
votes
1
answer
2k
views
Using spatial points to extract values from large raster in R
I am working with location data for 22 different individuals (id). The data contains an id column, and coordinates (UTM_x and UTM_y). For all individuals combined, there is a total of 991,099 ...
13
votes
1
answer
631
views
Creating animated light cone of a lighthouse and part of coastline covered by light in QGIS
As a follow up question to this: Hiding layer for N seconds in QGIS: animate symbols with custom intervals
Using QGIS 3.32, how can I animate a point layer using the new animated marker style in a way ...
1
vote
1
answer
251
views
Sample points from each feature in a featurecollection (Google Earth Engine)
I created a grid (featurecollection containing various rectangular features) by coveringGrid function, and now I want to sample 10 points within a feature, and for every feature in this ...
0
votes
0
answers
24
views
Exporting .LAS file after using v.lidar.correction
Question
I want to use the GRASS GIS LIDAR modules (v.lidar.edgedetection, v.lidar.growing, and v.lidar.correction) to classify points for LAS files. I'm very new to working with databases, and the ...
4
votes
4
answers
2k
views
How to delete duplicate LiDAR points?
How can I delete duplicate LiDAR points? I incorrectly read the same las twice and saved as a one file resulting in duplicate XY points. How should I delete these duplicate points?