Unverified Commit 5605b499 authored by Austin Sanders's avatar Austin Sanders Committed by GitHub
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Update quaternions to prevent sign flipping (#623) 



* Updated quaternion accessor to prevent unwanted sign flip

* Updated changelog

* flipped quaternion signs to follow new logic

---------

Co-authored-by: default avatarSanders <arsanders@igswza281l2314.gs.doi.net>
parent 396524c2

CHANGELOG.md

+1 −0
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ release. 
- Fixed incorrect distortion look up in Orex camera when working with PolyCam images [#583](https://github.com/DOI-USGS/ale/pull/583)

- Brought timing in line with ISIS for the KaguyaMiIsisLabelNaifSpiceDriver [#599](https://github.com/DOI-USGS/ale/pull/599)

- Brought timing in line with ISIS for the MroMarciIsisLabelNaifSpiceDriver [#600](https://github.com/DOI-USGS/ale/pull/600)

- Fixed a bug in which quaternions would flip sign in a way that caused interpolation errors [#603](https://github.com/DOI-USGS/ale/issues/603)



## [0.10.0] - 2024-01-08

ale/rotation.py

+21 −1
Original line number Diff line number Diff line
@@ -196,7 +196,27 @@ class TimeDependentRotation: 
        the destination reference frame. The quaternions are in scalar

        last format (x, y, z, w).

        """

        return self._rots.as_quat()

        quats = self._rots.as_quat()



        # First find the largest magnitude quaternion coefficient and its coordinate

        num_quats = len(quats)

        max_q = 0.0

        max_j = 0

        for i in range(num_quats):

            for j in range(4):

                if abs(quats[i][j]) > abs(max_q):

                    max_q = quats[i][j]

                    max_j = j



        # Ensure the signs are consistent

        qcnt = 0

        for i in range(num_quats):

            if quats[i][max_j] * max_q < 0:

                qcnt = qcnt + 1

                for j in range(4):

                    quats[i][j] *= -1.0



        return quats



    @quats.setter

    def quats(self, new_quats):

tests/pytests/data/isds/dawnvir_isd.json

+4 −4
Original line number Diff line number Diff line
@@ -339,10 +339,10 @@ 
    ],

    "quaternions": [

      [

        -0.08339426680875163,

        0.2825790922154143,

        -0.2899354389711647,

        0.9105667982826637

        0.08339426680875163,

        -0.2825790922154143,

        0.2899354389711647,

        -0.9105667982826637

      ],

      [

        -0.05753008804150366,