Set the default unit of configurations as meter

cyang-kth / fmm

Fast map matching, an open source framework in C++

https://fmm-wiki.github.io/

Apache License 2.0

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Set the default unit of configurations as meter #152

Closed cyang-kth closed 3 years ago

cyang-kth commented 3 years ago

It is legitimate to assume that

GPS data will always have the unit in degree
Road network will be in degree or meters, which can be inferred from the projection.

For map matching configuration, it is more straightforward to set unit as

r: search radius as meters, such as 100, 300
e: GPS error as meters, such as 50, 100, 200
delta: meters: 1000, 3000, 5000
vmax: km/h such as 80, 120

cyang-kth commented 3 years ago

The conversion should be quite easy in Python with multiplying and dividing by 1.132e5 and the above setting will cause extra confusion as current all units are in the map unit (degree).