geopandasgpspandaspython
I have a GeoPandas geodataframe with LineString geometries and I'd like to export them into .gpx files as GPS routes.
I've searched for hints in the web but found anything useful.
Are there GeoPandas specific way to do this or from other packages like Shapely?
May be off topic because it is a postgresql/postgis solution:
In postgres/postgis it is a simple O(N^2) query that may/could be adopted to geopanda.
$ psql gis_se;
-- create the postgis extension
create extension postgis;
-- create a polygon table
create table test_overlap(id serial primary key);
-- Add the geometry
select addgeometrycolumn('public','test_overlap','geom',4326,'POLYGON',2);
insert into test_overlap(geom) values
(ST_GeomFromEWKT('SRID=4326;POLYGON((-2 -2, -2 -1,-1 -1,-1 -2, -2 -2))')),
(ST_GeomFromEWKT('SRID=4326;POLYGON((-2 -2, -2 0, 0 0, 0 -2, -2 -2))')),
(ST_GeomFromEWKT('SRID=4326;POLYGON((2 2, 2 0, 0 0, 0 2, 2 2))')),
(ST_GeomFromEWKT('SRID=4326;POLYGON((2 2, 2 1,1 1,1 2, 2 2))')),
(ST_GeomFromEWKT('SRID=4326;POLYGON((-1.5 -1.5, -1.5 1.5,1.5 1.5,1.5 -1.5, -1.5 -1.5))'));
and defines 5 rectangles:
The intersection request with the table itself:
select a.id, b.id, st_intersects(a.geom, b.geom)
from test_overlap as a, test_overlap as b
where a.id<>b.id;
shows which areas intersecting each other:
id | id | st_intersects
----+----+---------------
1 | 2 | t
1 | 3 | f
1 | 4 | f
1 | 5 | t
2 | 1 | t
2 | 3 | t
2 | 4 | f
2 | 5 | t
3 | 1 | f
3 | 2 | t
3 | 4 | t
3 | 5 | t
4 | 1 | f
4 | 2 | f
4 | 3 | t
4 | 5 | t
5 | 1 | t
5 | 2 | t
5 | 3 | t
5 | 4 | t
Using this basis you can aggregate the counts for each ID object via the group by clausel:
select id, count(id)
from (select
a.id as id, b.id as bid,
st_intersects(a.geom, b.geom) as intersects
from test_overlap as a, test_overlap as b where a.id<>b.id
) as i
where intersects
group by id
order by id;
The result shows the wanted pattern.
id | count
----+-------
1 | 2
2 | 3
3 | 3
4 | 2
5 | 4
The GeoPandas plotting methods are there for convenience. They do override the standard pandas plotting methods. For now, the easiest way to get access to basic pandas plotting is probably through their functional versions, something like this:
from pandas.tools.plotting import plot_frame
plot_frame(mygeodataframe, kind='scatter', ...)
Feel free to create an issue about this on the GitHub repository (or better yet, help implement a solution).
Best Answer
To test my approach, I loaded a shapefile as GeoPandas geodataframe and, afterwards, I saved it as gpx file. This is the code:
When gpx layer is loaded at Map Canvas, it could be observed that it works perfectly.