Questions tagged [st-makeline]
A function that forms a line from a set of points (or other geometries).
15 questions
2
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1
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28
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How do I use SQL and virtual layer to draw a line from one polygon to another in the same layer?
Background:
Sometimes in modelling hydrology (e.g. in SWMM) we have runon from one subcatchment area to another. These subcatchments are records in a shapefile. I want to show this situation as a line ...
5
votes
1
answer
205
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Creating LineString from points by group of time period using SQL
I have a serie of GPS points with dates and a state ('flying' or 'grown') from different individuals.
I would like to get lines from those points by individual, grouped by state BUT still ordered by ...
- 163
1
vote
0
answers
126
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QGIS specified make_line curved between points
This question is a continuation of this answer
I want to draw curved lines between specific points that are related to each other.
On my points layer each point has:
unique FID and relation field to ...
- 486
1
vote
0
answers
359
views
QGIS Geometry Generator make_line using road network
I want in QGIS 3.22 Geometry Generator to connect related points with a line, but the line must go between the points along the shortest network of paths.
I have two layers:
one is "points" ...
- 486
4
votes
1
answer
212
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Gaps and Islands problem in PostGIS for GPS traces
I'm using ST_MakeLine to create traces of ship movements. The query below yields all the GPS points on a certain day, and I'm using ST_Within to only find ships in the navigable portions of the river.
...
- 103
1
vote
1
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121
views
Make line geom from two point columns which are the result of a join
I have the following query which joins two tables and returns two geom columns, I would now like to make a line between the two geom columns and set that as the Geom for the Drops table.
Table 1 - ...
- 67
2
votes
1
answer
291
views
create lines from points table
I have a point table I have sorted by mmsi (it is the identifier) and by datetime columns.
mmsi numeric,
x1 double precision,
y1 double precision,
datetime timestamp without time zone,
geom ...
- 131
0
votes
1
answer
156
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How to Use ST_MakeLine query in leaflet to connect to Carto
I want to run in leaflet a query that works in carto Builder to connect points in a line:
SELECT ST_MakeLine(the_geom_webmercator) as the_geom_webmercator, min(cartodb_id) as cartodb_id FROM my_table
...
- 21
1
vote
0
answers
46
views
How to obtain a live route on a carto map? [duplicate]
My main goal is to build an app that send lat lon from my smartphone to my carto (postgis) database and show the route "live" (in real time) as a line and not as a lot of points.
i am able to save ...
- 21
1
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0
answers
1k
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What to add as "measure" to a linestringM in PostGIS?
I am kind of new into the GIS world. I have a couple of GPS data in a CSV file as LonLat coordinates.
I used PostGIS to create points from those coordinates using ST_MakePoint().
Then I tried to ...
- 11
4
votes
1
answer
661
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QGIS make lines with offsets of y and azimuth from source and target coordinates
I'm very new with QGIS and currently stuck with such problem in my work. Maybe some one knows how to help me?
I have made two separate layers.
Database layer with sites and antennas, containing ...
- 43
3
votes
1
answer
3k
views
PostgreSQL create line from points
How do i create a linestring from points sort by date in PostgreSQL?
I tried:
SELECT observations.id,
ST_MakeLine(observations.geom ORDER BY observations.date) AS newgeom
FROM observations
...
1
vote
0
answers
27
views
PostgreSQL points to line error [duplicate]
I have GPS locations with date. These are points.
I want to convert the points to lines, sorted by date.
Using PostgreSQL
Tried:
SELECT observations.id,
ST_MakeLine(observations.geom ORDER ...
2
votes
2
answers
457
views
PostGIS MakeLine issue
I am using GPS coordinates and I am trying to create lines (routes) from lon,lat.
I create a geography column from my point and then I create the line as following:
ST_MakeLine(point_geom order by ...
3
votes
1
answer
385
views
Displaying lines in QGIS from ST_MakeLine() not working with UPDATE, but works with CREATE TABLE
When using UPDATE to create geometries based on the SCHNUM (school number) of students to their attend school, not all the lines show up in QGIS. However, when the basic query result is written to a ...
- 18.9k