@indoor-analytics/path-distance

Computes distance between two paths by projecting positions of the second (acquired) path onto the first (reference) one. This allows to compare paths with different location counts.

comparing two paths	comparing same paths with time information taken into account

How to use

Add this line to ~/.npmrc to set up the package registry:

@indoor-analytics:registry=https://npm.pkg.github.com/indoor-analytics

In your project, install the package:

npm i --save @indoor-analytics/path-distance

Import the function in your code:

import {pathDistance} from '@indoor-analytics/path-distance';

Algorithms

Classic distance

For each acquired path location, we create a projection on the reference path; first path location will always match first reference path, the same for the last location.

A projected position is obtained by:

1. getting distance between the current path position and the path origin;
2. computing the ratio position distance / path length;
3. computing the equivalent distance regarding the reference path;
4. projecting the position on the reference path.

Timed distance

For each path reference path segment (made by two consecutive path points):

1. get both points' timestamps;
2. get compared path segment whose locations have been captured while walking current reference path segment;
3. compare reference path segment and compared path segment using classic distance algorithm