Celx: difference between Position and Vector objects?

[Rjp buisson]

In Lua-Celx programming:

Is a 'position' object the same class as a 'vector' ???
Do the same methods apply to both of them?
If not, WHAT is exactly a Position object?
Thanks

[Harry]

In Lua-Celx programming:

Is a 'position' object the same class as a 'vector' ???
Do the same methods apply to both of them?
If not, WHAT is exactly a Position object?

Today must be the record for the number of CELX-related questions

Position and Vector are similar, but not the same. Both contain three components, but with different precision - a Position contains three 128-Bit numbers, which is enough to cover the universe up to ~1e19 ly (?) away from our Sun with uniformly high precision. A vector is made of three double-precision floating point numbers, which makes the precision suffer for very long vectors.

You should think of a vector as pointing from one position to another (e.g. if you compute the difference between two positions in CELX, the result will be a vector). However sometimes it makes sense to (mis)use one for the other.

Harald

[don]

Today must be the record for the number of CELX-related questions

We just didn't want you to feel left out Harald.

[Rjp buisson]

Hi Harry
Hello Don
Thanks a lot for your prompt answers.
You do make a great job watching and answering our mail..
Clear skyes to you.
JPierre