cozy-client / models / geo
Namespace: geo¶
models.geo
Functions¶
computeSpeed¶
▸ computeSpeed(distance, duration): number
Compute the speed from distance and duration
Parameters
| Name | Type | Description |
|---|---|---|
distance |
number |
The distance in meters |
duration |
number |
The duration in seconds |
Returns
number
- The speed, in m/s, rounded to 2 decimals
Defined in
packages/cozy-client/src/models/geo.js:12
computeSphericalCenter¶
▸ computeSphericalCenter(coordinates): Coordinates
Compute the geographical center of the given points
This consists of finding the centroid of a set of points in a sphere. Note this assumes the Earth is a perfect sphere, which is not, but the approximation should be good enough.
Parameters
| Name | Type | Description |
|---|---|---|
coordinates |
Coordinates[] |
The geo points |
Returns
Coordinates
The center point
Defined in
packages/cozy-client/src/models/geo.js:104
deltaLatitude¶
▸ deltaLatitude(distance): number
Compute the latitude delta from a distance, in meters.
The reasoning is rather simple: there are 360° of latitudes of same distance. Then, it consists of computing 1 degree distance, and divide the given distance by this value.
Parameters
| Name | Type | Description |
|---|---|---|
distance |
number |
The distance in meters |
Returns
number
The delta latitude degrees
Defined in
packages/cozy-client/src/models/geo.js:172
deltaLongitude¶
▸ deltaLongitude(latitude, distance): number
Compute the longitude delta from a distance, in meters.
This requires the latitude: we want to compute the horizontal delta on the Earth surface. As it is a sphere (kind of), this delta won’t be the same depending on whether it is on the equator (min variation) or on the poles (max variation), for instance.
Parameters
| Name | Type | Description |
|---|---|---|
latitude |
number |
The latitude |
distance |
number |
The distance in meters |
Returns
number
the longitude delta degrees
Defined in
packages/cozy-client/src/models/geo.js:155
geodesicDistance¶
▸ geodesicDistance(point1, point2): number
Compute the distance between 2 geographic points, in meters.
This is an implementation of the Haversine formula, that supposes a perfect sphere. We know this is not exactly the case for Earth, especially at the poles, but this approximation is good enough. More complex methods do exist, such as Vincenty formula, but we prefer simplicity over precision here. See https://en.wikipedia.org/wiki/Geodesics_on_an_ellipsoid
Parameters
| Name | Type | Description |
|---|---|---|
point1 |
Coordinates |
The first point coordinates, in decimal degrees |
point2 |
Coordinates |
The second point coordinates, in decimal degrees |
Returns
number
The distance between the points, in meters, rounded to 2 decimals
Defined in