How to create a linestring from a geopandas data frame?

Question

I am trying to create a linestring from a geopandas dataframe with points as geometries

date_time latitude longitude year data01 hour minute data02
0 2019年11月08日 08:21:38 36.830444 -2.466583 2019 312 8 21 0
1 2019年11月08日 08:32:15 36.830250 -2.466611 2019 312 8 32 0
2 2019年11月08日 08:41:51 36.830417 -2.466778 2019 312 8 41 0
3 2019年11月08日 08:51:53 36.830361 -2.466833 2019 312 8 51 0
4 2019年11月08日 09:01:50 36.830528 -2.466806 2019 312 9 1 0

using the this code:

 date_time latitude longitude year data01 hour minute data02 geometry
0 2019年11月08日 08:21:38 36.830444 -2.466583 2019 312 8 21 0 POINT (-2.466583 36.830444)
1 2019年11月08日 08:32:15 36.830250 -2.466611 2019 312 8 32 0 POINT (-2.466611 36.83025)
2 2019年11月08日 08:41:51 36.830417 -2.466778 2019 312 8 41 0 POINT (-2.466778 36.830417)
3 2019年11月08日 08:51:53 36.830361 -2.466833 2019 312 8 51 0 POINT (-2.466833 36.830361)
4 2019年11月08日 09:01:50 36.830528 -2.466806 2019 312 9 1 0 POINT (-2.466806 36.830528)
geo_df = geo_df.groupby(['date_time'])['geometry'].apply(lambda x: LineString(x.tolist()))
geo_df = GeoDataFrame(geo_df, geometry='geometry')

Error: ValueError: LineStrings must have at least 2 coordinate tuples

How can I do that ? or can I create the linestring using just the latitude and longitude columns?

Even if use geopandas to convert to linestring geometry the columns look no good for that

geometry = [LineString(xy) for xy in zip(df.longitude, df.latitude)]
geo_df = GeoDataFrame(df, geometry=geometry)
geo_df
 ValueError: Input (-2.466583, 36.830444) is the wrong shape for a LineString

Answer 1

With all your solutions, you try to create a LineString with only one point

Since all the dates (hours) are different:

geo_df = geo_df.groupby(['date_time'])
print("number of groups:", geo_df.ngroups)
number of groups: 5 # and 5 original geometries
for group in gdf.groupby(['date_time']).geometry:
 print(group)
(Timestamp('2019-11-08 08:21:38'), 0 POINT (-2.466583 36.830444)
 Name: geometry, dtype: object)
(Timestamp('2019-11-08 08:32:15'), 1 POINT (-2.466611 36.83025)
Name: geometry, dtype: object)
(Timestamp('2019-11-08 08:41:51'), 2 POINT (-2.466778 36.830417)
Name: geometry, dtype: object)
(Timestamp('2019-11-08 08:51:53'), 3 POINT (-2.466833 36.830361)
Name: geometry, dtype: object)
(Timestamp('2019-11-08 09:01:50'), 4 POINT (-2.466806 36.830528)
Name: geometry, dtype: object)

Only one point per group -> Error: ValueError: LineStrings must have at least 2 coordinate tuples)

And

geometry = [xy for xy in zip(df.longitude, df.latitude)]
print(geometry)
[(-2.466583, 36.830444), (-2.466611, 36.83025), (-2.4667779999999997, 36.830417), (-2.4668330000000003, 36.830360999999996), (-2.466806, 36.830528)
# geometry is a list of point coordinates
Point(geometry[0]).wkt
'POINT (-2.466583 36.830444)'
#but
LineString(geometry[0])
...

ValueError: Input (-2.466583, 36.830444) is the wrong shape for a LineString

And I suppose you want to create a line with all the points, therefore

 print(LineString(geometry).wkt)
 LINESTRING (-2.466583 36.830444, -2.466611 36.83025, -2.466778 36.830417, -2.466833 36.830361, -2.466806 36.830528)

or directly

print(LineString(df.geometry).wkt)
LINESTRING (-2.466583 36.830444, -2.466611 36.83025, -2.466778 36.830417, -2.466833 36.830361, -2.466806 36.830528) 

If you want to use groupby to create separate lines choose another column to regroup (look at Turning GeoDataFrame of x,y coordinates into Linestrings using GROUPBY? or Convert Points to Lines Geopandas)

with data02 modified (2 groups, 0 and 1)

date_time,latitude,longitude,year,data01,hour,minute,data02,wtkcolumn
2019年11月08日 08:21:38,36.830444,-2.466583, 2019, 312, 8 , 21 , 0 , POINT (-2.466583 36.830444)
2019年11月08日 08:32:15,36.830250,-2.466611, 2019, 312, 8 , 32, 0, POINT (-2.466611 36.83025)
2019年11月08日 08:41:51 ,36.830417,-2.466778, 2019, 312, 8 , 41 , 1 , POINT (-2.466778 36.830417)
2019年11月08日 08:51:53 ,36.830361,-2.466833, 2019, 312, 8, 51, 1 , POINT (-2.466833 36.830361)
2019年11月08日 09:01:50, 36.830528, -2.466806, 2019, 312, 9 , 1 , 1, POINT (-2.466806 36.830528)
list(geo_df.groupby(['data02'])['geometry'].apply(lambda x: LineString(x.tolist())))
[<shapely.geometry.linestring.LineString object at 0x11bc81668>, <shapely.geometry.linestring.LineString object at 0x11bc81400>]

• mmann1123: For more on creating spatial objects you might look here pygis.io/docs/e_new_vectors.html