/usr/include/ is in libignition-math2-dev 2.9.0+dfsg1-1.
This file is owned by root:root, with mode 0o755.
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/usr/include/ignition/
/usr/include/ignition/math2/
/usr/include/ignition/math2/ignition/
/usr/include/ignition/math2/ignition/math/
/usr/include/ignition/math2/ignition/math/AffineException.hh
/usr/include/ignition/math2/ignition/math/Angle.hh
/usr/include/ignition/math2/ignition/math/Box.hh
/usr/include/ignition/math2/ignition/math/Color.hh
/usr/include/ignition/math2/ignition/math/Filter.hh
/usr/include/ignition/math2/ignition/math/Frustum.hh
/usr/include/ignition/math2/ignition/math/Helpers.hh
/usr/include/ignition/math2/ignition/math/IndexException.hh
/usr/include/ignition/math2/ignition/math/Inertial.hh
/usr/include/ignition/math2/ignition/math/Kmeans.hh
/usr/include/ignition/math2/ignition/math/Line2.hh
/usr/include/ignition/math2/ignition/math/Line3.hh
/usr/include/ignition/math2/ignition/math/MassMatrix3.hh
/usr/include/ignition/math2/ignition/math/Matrix3.hh
/usr/include/ignition/math2/ignition/math/Matrix4.hh
/usr/include/ignition/math2/ignition/math/OrientedBox.hh
/usr/include/ignition/math2/ignition/math/PID.hh
/usr/include/ignition/math2/ignition/math/Plane.hh
/usr/include/ignition/math2/ignition/math/Pose3.hh
/usr/include/ignition/math2/ignition/math/Quaternion.hh
/usr/include/ignition/math2/ignition/math/Rand.hh
/usr/include/ignition/math2/ignition/math/RotationSpline.hh
/usr/include/ignition/math2/ignition/math/SemanticVersion.hh
/usr/include/ignition/math2/ignition/math/SignalStats.hh
/usr/include/ignition/math2/ignition/math/SphericalCoordinates.hh
/usr/include/ignition/math2/ignition/math/Spline.hh
/usr/include/ignition/math2/ignition/math/Temperature.hh
/usr/include/ignition/math2/ignition/math/Triangle.hh
/usr/include/ignition/math2/ignition/math/Triangle3.hh
/usr/include/ignition/math2/ignition/math/Vector2.hh
/usr/include/ignition/math2/ignition/math/Vector3.hh
/usr/include/ignition/math2/ignition/math/Vector3Stats.hh
/usr/include/ignition/math2/ignition/math/Vector4.hh
/usr/include/ignition/math2/ignition/math/config.hh
/usr/include/ignition/math2/ignition/math.hh