Map constrctions with python, plotly and dash

Dash Python
1

Is it possible to construct route ways from current location to destination. Right now I’m just joining two locations with a line. I know it’s not good. Can we make a model such that, it should show the exact way on how to reach the destination from current location.

Something like this:

from_and_to
from_and_to.jpg1760×1020 565 KB

Not showing all the details as google maps show, but just highlighting the route on how to reach the destination.

2

If the question is how to plot a route on the map - one way to do it is by using Scattermapbox.

results in something like this - http://velometria.com/activity/1354978421

here is the snippet:

import plotly.graph_objs as go

go.Scattermapbox(
    lat=list(data_frame['lat']),
    lon=list(data_frame['lng']),
    visible=visible,
    mode='markers',
    marker=go.Marker(
        size=kwargs.get('marker_size', 5),
        color=data_frame[column_name],
    ),
    hoverinfo='text',
)
3

This reply gave me some intuition, but I need something like, when I pass the latitudes and longitudes of two locations, it should trace out the exact route on how to reach there. I will look into your solution and try out.

Please see this

Thanks

4

I would say that the actual routing calculation is out of the plotly scope. I would rather look into https://developers.google.com/maps/documentation/directions/ for example and used plotly to display the resulting polyline (must be decoded into (lat, lon) pairs before use).

1 Like
5

Or checkout Mapbox’s APIs

6

Finally I’m able to display the exact route from home to destination place.

exact_route
exact_route.png1227×563 169 KB

1 Like
7

That looks promising, @syntaxError! I’m looking for a similar solution, can you share how did you achieve that? I’m currently looking into the Mapbox Directions API

8

Basically I am using openweathermap API to capture the location coordinates of From place and To place. Thereafter, using mapbox API, I capture the route. To highlight the route, again we need coordinates to join them all as a line.

def get_location(name):
	name = name.lower()
	url = 'http://api.openweathermap.org/data/2.5/weather?q='+str(name)+'&appid='+str(<your_openweathermap_api>)
	open_url = urllib2.urlopen(url)
	open_w = json.load(open_url)
	ll = [i[1] for i in open_w['coord'].items()]
	lat = ll[0]
	lon = ll[1]
	return lat, lon

def map_locations(home, dest):
	initial_lat, initial_lon = get_location(home)
	final_lat, final_lon = get_location(dest)
	return initial_lat, initial_lon, final_lat, final_lon

We make use of the above functions to capture the coordinates of From and To.

To capture the coordinates of the route path, we need to use of mapbox API.

def get_route(home, dest, travelling_mode):
	initial_lat, initial_lon, final_lat, final_lon = map_locations(home, dest)

	mapurl = 'https://api.mapbox.com/directions/v5/mapbox/' + str(travelling_mode) + '/' + str(initial_lon) + ',' + str(initial_lat) + ';' + str(final_lon) + ',' + str(final_lat) + '?geometries=geojson&access_token=' + str(<your_mapbox_api>)
	openmap = urllib2.urlopen(mapurl)
	mapjs = json.load(openmap)

	lons = []
	lats = []

	for ks in mapjs['routes']:
		for k, v in ks.items():
			if k == 'geometry':
				for eachk, eachv in v.items():
					if eachk == 'coordinates':
						for eachloc in eachv:
							lons.append(eachloc[0])
							lats.append(eachloc[1])

	return lats, lons

# print(get_route('hyderabad', 'chennai', 'driving'))

And finally we have to plot them all.

lats, lons = get_route(`home`, `dest`, `travelling_mode`)
go.Scattermapbox(
	lat=lats,
	lon=lons,
	mode='lines',
	line=dict(width=2),
	marker=dict(
		size=5,
	),
       text='{} to {} : {}'.format(str(`home`).title(), str(`dest`).title(), str(`travelling_mode`).title()),
       hoverinfo='text'
)

MapBox provides 3 types of traveling mode - Driving, Cycling and Walking. Make sure to have the api keys to get the data.

Hope this will solve your issue.

3 Likes
9

@syntaxError, thank you very much for sharing this!