Analytics

visualization

class pytrack.analytics.visualization.Map(location=None, width='100%', height='100%', left='0%', top='0%', position='relative', tiles='CartoDB positron', attr=None, min_zoom=0, max_zoom=18, zoom_start=15, min_lat=- 90, max_lat=90, min_lon=- 180, max_lon=180, max_bounds=False, crs='EPSG3857', control_scale=False, prefer_canvas=False, no_touch=False, disable_3d=False, png_enabled=False, zoom_control=True, **kwargs)[source]

Bases: Map

This class extends the folium.Map to add functionality useful to represent graphs and road paths.

Parameters

  • location (tuple or list, optional, default: None) – Latitude and Longitude of Map (Northing, Easting).

  • width (int or percentage string, optional, default: '100%')) – Width of the map.

  • height (int or percentage string, optional, default: '100%') – Height of the map.

  • tiles (str, optional, default: 'OpenStreetMap') – Map tileset to use. Can choose from a list of built-in tiles, pass a custom URL or pass None to create a map without tiles. For more advanced tile layer options, use the TileLayer class.

  • min_zoom (int, optional, default: 0) – Minimum allowed zoom level for the tile layer that is created.

  • max_zoom (int, optional, default: 18) – Maximum allowed zoom level for the tile layer that is created.

  • zoom_start (int, optional, default 10) – Initial zoom level for the map.

  • attr (string, optional, default: None) – Map tile attribution; only required if passing custom tile URL.

  • crs (str, optional, default: 'EPSG3857') – Defines coordinate reference systems for projecting geographical points into pixel (screen) coordinates and back. You can use Leaflet’s values : * EPSG3857 : The most common CRS for online maps, used by almost all free and commercial tile providers. Uses Spherical Mercator projection. Set in by default in Map’s crs option. * EPSG4326 : A common CRS among GIS enthusiasts. Uses simple Equirectangular projection. * EPSG3395 : Rarely used by some commercial tile providers. Uses Elliptical Mercator projection. * Simple : A simple CRS that maps longitude and latitude into x and y directly. May be used for maps of flat surfaces (e.g. game maps). Note that the y axis should still be inverted (going from bottom to top).

  • control_scale (bool, optional, default: False) – Whether to add a control scale on the map.

  • prefer_canvas (bool, optional, default: False) – Forces Leaflet to use the Canvas back-end (if available) for vector layers instead of SVG. This can increase performance considerably in some cases (e.g. many thousands of circle markers on the map).

  • no_touch (bool, optional, default: False) – Forces Leaflet to not use touch events even if it detects them.

  • disable_3d (bool, optional, default: False) – Forces Leaflet to not use hardware-accelerated CSS 3D transforms for positioning (which may cause glitches in some rare environments) even if they’re supported.

  • zoom_control (bool, optional, default: True) – Display zoom controls on the map.

  • **kwargs (keyword arguments, optional, default: no attributes) – Additional keyword arguments are passed to Leaflets Map class: https://leafletjs.com/reference-1.6.0.html#map

Return type

Folium Map Object

Notes

See https://github.com/python-visualization/folium/blob/551b2420150ab56b71dcf14c62e5f4b118caae32/folium/folium.py#L69 for a more detailed description

add_child(child, name=None, index=None)

Add a child.

add_children(child, name=None, index=None)

Add a child.

add_graph(G, plot_nodes=False, edge_color='#3388ff', edge_width=3, edge_opacity=1, radius=1.7, node_color='red', fill=True, fill_color=None, fill_opacity=1)[source]

Add the road network graph created with pytrack.graph.graph.graph_from_bbox method

Parameters

  • G (networkx.MultiDiGraph) – Road network graph.

  • plot_nodes (bool, optional, default: False) – If true, it will show the vertices of the graph.

  • edge_color (str, optional, default: "#3388ff") – Colour of graph edges

  • edge_width (float, optional, default: 3) – Width of graph edges

  • edge_opacity (float, optional, default: 1) – Opacity of graph edges

  • radius (float, optional, default: 1.7) – Radius of graph vertices

  • node_color (str, optional, default: "red") – Colour of graph vertices

  • fill (bool, optional, default: True) – Whether to fill the nodes with color. Set it to false to disable filling on the nodes.

  • fill_color (str or NoneType, default: None) – Fill color. Defaults to the value of the color option.

  • fill_opacity (float, optional, default: 1) – Fill opacity

add_to(parent, name=None, index=None)

Add element to a parent.

choropleth(*args, **kwargs)[source]

Call the Choropleth class with the same arguments.

This method may be deleted after a year from now (Nov 2018).

default_css = [('leaflet_css', 'https://cdn.jsdelivr.net/npm/leaflet@1.6.0/dist/leaflet.css'), ('bootstrap_css', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css'), ('bootstrap_theme_css', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap-theme.min.css'), ('awesome_markers_font_css', 'https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css'), ('awesome_markers_css', 'https://cdnjs.cloudflare.com/ajax/libs/Leaflet.awesome-markers/2.0.2/leaflet.awesome-markers.css'), ('awesome_rotate_css', 'https://cdn.jsdelivr.net/gh/python-visualization/folium/folium/templates/leaflet.awesome.rotate.min.css')]
default_js = [('leaflet', 'https://cdn.jsdelivr.net/npm/leaflet@1.6.0/dist/leaflet.js'), ('jquery', 'https://code.jquery.com/jquery-1.12.4.min.js'), ('bootstrap', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js'), ('awesome_markers', 'https://cdnjs.cloudflare.com/ajax/libs/Leaflet.awesome-markers/2.0.2/leaflet.awesome-markers.js')]
draw_candidates(candidates, radius)[source]

Draw the candidate nodes of the HMM matcher

Parameters

  • candidates (dict) – Candidates’ dictionary computed via pytrack.matching.candidate.get_candidates method

  • radius (float) – Candidate search radius

draw_path(G, trellis, predecessor, path_name='Matched path')[source]

Draw the map-matched path

Parameters

  • G (networkx.MultiDiGraph) – Road network graph.

  • trellis (nx.DiGraph) – Trellis DAG graph created with pytrack.matching.mpmatching_utils.create_trellis method

  • predecessor (dict) – Predecessors’ dictionary computed with pytrack.matching.mpmatching.viterbi_search method

  • path_name (str) – Name of the path to be drawn

fit_bounds(bounds, padding_top_left=None, padding_bottom_right=None, padding=None, max_zoom=None)[source]

Fit the map to contain a bounding box with the maximum zoom level possible.

Parameters

  • bounds (list of (latitude, longitude) points) – Bounding box specified as two points [southwest, northeast]

  • padding_top_left ((x, y) point, default None) – Padding in the top left corner. Useful if some elements in the corner, such as controls, might obscure objects you’re zooming to.

  • padding_bottom_right ((x, y) point, default None) – Padding in the bottom right corner.

  • padding ((x, y) point, default None) – Equivalent to setting both top left and bottom right padding to the same value.

  • max_zoom (int, default None) – Maximum zoom to be used.

Examples

>>> m.fit_bounds([[52.193636, -2.221575], [52.636878, -1.139759]])
get_bounds()

Computes the bounds of the object and all it’s children in the form [[lat_min, lon_min], [lat_max, lon_max]].

get_name()

Returns a string representation of the object. This string has to be unique and to be a python and javascript-compatible variable name.

get_root()

Returns the root of the elements tree.

keep_in_front(*args)[source]

Pass one or multiple layers that must stay in front.

The ordering matters, the last one is put on top.

Parameters

*args – Variable length argument list. Any folium object that counts as an overlay. For example FeatureGroup or TileLayer. Does not work with markers, for those use z_index_offset.

render(**kwargs)[source]

Renders the HTML representation of the element.

save(outfile, close_file=True, **kwargs)

Saves an Element into a file.

Parameters

  • outfile (str or file object) – The file (or filename) where you want to output the html.

  • close_file (bool, default True) – Whether the file has to be closed after write.

to_dict(depth=- 1, ordered=True, **kwargs)

Returns a dict representation of the object.

to_json(depth=- 1, **kwargs)

Returns a JSON representation of the object.

pytrack.analytics.visualization.draw_trellis(T, figsize=None, dpi=None, node_size=500, font_size=8, **kwargs)[source]

Draw a trellis graph

Parameters

  • T (networkx.DiGraph) – A directed acyclic graph

  • figsize ((float, float), optional, default: [15.0, 12.0]) – Width, height figure size tuple in inches, optional

  • dpi (float, optional, default: 300.0) – The resolution of the figure in dots-per-inch

  • node_size (scalar or array, optional, default: 500) – Size of nodes. If an array is specified it must be the same length as nodelist.

  • font_size (int, optional, default: 8) – Font size for text labels

  • kwargs (keyword arguments, optional, default: no attributes) – See networkx.draw_networkx_nodes(), networkx.draw_networkx_edges(), networkx.draw_networkx_labels() and matplotlib.pyplot.figure() for a description of optional keywords.

Returns

trellis_diag – Graphical illustration of the Trellis diagram used in the Hidden Markov Model process to find the path that best matches the actual GPS data

Return type

matplotlib.pyplot.Figure

video

plugins

class pytrack.analytics.plugins.Segmenter[source]

Skeleton parent class to perform the segmentation operation.

processing(img)[source]

It takes an input image and returns the processed image.

run(img)[source]

It takes an input image and returns the mask of the segmented image.