MarkerPCA

MLModule

genre	Marker
author	MeVis Medical Solutions AG
package	MeVisLab/Standard
dll	MLGeometry1
definition	MLGeometry1.def
keywords	XMarker, main, axis, bounding, box

Purpose

The MarkerPCA module performs a principal component analysis (PCA) of the 3D positions of the markers. The resulting eigenvectors and eigenvalues are sorted so that the largest eigenvalue appears first.

Input Fields

inMarkerList

name: inMarkerList, type: XMarkerList(MLBase)

The input markers list.

For accessing this object via scripting, see the Scripting Reference: MLXMarkerListWrapper.

Parameter Fields

Field Index

Center: Vector3	Update: Trigger
Center Of Mass: Vector3	Valid: Bool
Longest Axis: Vector3
Longest Extent: Float
Middle Axis: Vector3
Middle Extent: Float
Shortest Axis: Vector3
Shortest Extent: Float

Visible Fields

Longest Axis

name: longestAxis, type: Vector3, persistent: no

Shows the longest axis (normalized).

Middle Axis

name: middleAxis, type: Vector3, persistent: no

Shows the middle axis (normalized).

Shortest Axis

name: shortestAxis, type: Vector3, persistent: no

Shows the shortest axis (normalized).

Longest Extent

name: longestExtent, type: Float, persistent: no

Shows the extent along the longest axis.

Middle Extent

name: middleExtent, type: Float, persistent: no

Shows the extent along the middle axis.

Shortest Extent

name: shortestExtent, type: Float, persistent: no

Shows the extent along the shortest axis.

Center

name: center, type: Vector3, persistent: no

Shows the center (also known as the midpoint). This can be used to calculate or render the object-aligned bounding box by adding or subtracting the axes multiplied by half of their extent.

Center Of Mass

name: centerOfMass, type: Vector3, persistent: no

Shows the center of mass (also known as barycenter).

Update

name: update, type: Trigger

If triggered, the PCA is calculated.

Valid

name: valid, type: Bool, persistent: no

Shows whether the results are currently valid.