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Losing sign of quaternion

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Documentation
Clarity
Needs clarification
Activity status
Stale
Tech stack
c
Domain
embedded-iot

Research direction

Start with lsm6dsv16bx_STdC/examples/lsm6dsv16bx_sensor_fusion.c at line 182 and trace how the SFLP quaternion values are produced and normalized. Check the sensor documentation or related driver definitions for the fourth component and sign convention; done means documenting a clear explanation of whether the sign information is lost.

Written by the indexing model from the issue text.

Description

Could someone please explain what is the output of the SFLP quaternion block?
I see three half-floats are generated, and the fourth component is inferred from the game rotation being normalized.
Is the fourth component the real part? Don't we lose the sign with this transformation?

https://github.com/STMicroelectronics/STMems_Standard_C_drivers/blob/8d7095f3891b2684585176692e6aca7945f1d77e/lsm6dsv16bx_STdC/examples/lsm6dsv16bx_sensor_fusion.c#L182

Dominant language
C
Stars
882
Forks
539
PR merge metrics
No merged PRs in 30d

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