from_latlongalt

[gwbres]

Hello,

we have replaced everything we used from the map_3d library by ANISE. But we have lost the ability to describe an (RX) Orbit from (latitude, longitude) duplets, which is very convenient to the end user in geodesy.

It is very important for us to have such a feature. It seems this method is only available in python using your library

[ChristopherRabotin]

Hi Guillaume,

The from_latlongalt function is available in Rust: https://docs.rs/anise/latest/anise/math/cartesian/struct.CartesianState.html#method.from_latlongalt . However, it requires more than the latitude and longitude because it builds both the position and velocity vector on the provided frame, and therefore it needs the angular velocity of the point in that frame. For that reason, the mean angular velocity of the Earth is provided in the constants: https://docs.rs/anise/latest/anise/constants/usual_planetary_constants/constant.MEAN_EARTH_ANGULAR_VELOCITY_DEG_S.html .

I hope this helps.

[gwbres]

The from_latlongalt function is available in Rust:

I'm using v0.5.2 "as is"

However, it requires more than the latitude and longitude because it builds both the position and velocity vector on the provided

i'm not interested (at this point) by the velocity vector, so I usually tie to null the upper part of the vector

therefore it needs the angular velocity of the point in that frame. For that reason, the mean angular velocity of the Earth is provided in the constants: https://docs.rs/anise/latest/anise/constants/usual_planetary_constants/constant.MEAN_EARTH_ANGULAR_VELOCITY_DEG_S.html .

thank you very much, this will save me a lot of time. Continuing previous point i was thinking I would simply set a null angular velocity, this would not have worked

[ChristopherRabotin]

Sorry, you're right, the function in Rust is try_latlongalt because it returns a Result.

You should be able to set the mean angular velocity to zero, and that will zero out the velocity vector. Most orbital element computations on a state with a zero velocity vector will return a PhysicsError.

[gwbres]

oh thanks ! I will try this out.
I have grown to use "VS Code" for Rust coding, but it was unable to pick this up.
I also have the feeling that our workspace(s)/toolkit is too complex for it, it gets "overwhelmed" and very slow to operate

[gwbres]

I confirm this works, thanks for the support