Array and Matrix Functions

Arrays

Vector

Vector(a,b, etc)

creates a vector of the number of components specified

! Create a metric signal with 2 components and one frame

[Metric_Explicit]

! /RESULT_METRIC_FOLDER=PROCESSED

/RESULT_METRIC_NAME=VEC2

/METRIC_VALUE=2+3

;

! Create a vector containing a constant, a two dimensional metric and a 3 dimensional model based signal.

Evaluate_Expression

/EXPRESSION=vector (1, METRIC::PROCESSED::VEC2, LINK_MODEL_BASED::ORIGINAL::RKNEE_ANGLE)

! /SIGNAL_TYPES=

! /SIGNAL_FOLDER=ORIGINAL

! /SIGNAL_NAMES=

! /RESULT_TYPES=DERIVED

! /RESULT_FOLDERS=PROCESSED

/RESULT_NAME=TEST

! /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=FALSE

;

The resulting signal will have the first three columns (one for the constant, one for the vector of 2 components) buffered to the number of frames of RKNEE_ANGLE by replicating the first frame.

List

list(a,b,etc) -- creates a list (column vector) of the number of rows specified:

Unit_Vector

unit_vector (a, b, etc) -- creates a unit vector of the number of components specified:

Rotation Matrices

Rotation Multiply

Rotation_Multiply(a,b)

Example: Multiply two ROTATION signals

Evaluate_Expression

/EXPRESSION=ROTATION_MULTIPLY(ROTATION_INVERSE(ROTATION::ORIGINAL::PELVIS_SHIFTED_4x4),CURRENT_SIGNAL)

/SIGNAL_TYPES=ROTATION

! /SIGNAL_FOLDER=ORIGINAL

! /SIGNAL_NAMES=

/RESULT_TYPES=ROTATION

! /RESULT_FOLDERS=PROCESSED

/RESULT_NAME=_MULT

/APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE

;

Rotation Inverse

Rotation_Inverse(a)

Example: Inverse of a 4x4 ROTATION signal or a 3x3 LINK_MODEL_BASED ROTATION

A good description of the inverse of a ROTATION signals can be found [here]

Evaluate_Expression

/EXPRESSION=ROTATION_INVERSE(ROTATION::ORIGINAL::PELVIS_SHIFTED_4x4)

/SIGNAL_TYPES=ROTATION

! /SIGNAL_FOLDER=ORIGINAL

! /SIGNAL_NAMES=

/RESULT_TYPES=ROTATION

! /RESULT_FOLDERS=PROCESSED

/RESULT_NAME=_INV

/APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE

;

Rotation Transpose

Rotation_Transpose(a)

Example: Transpose of a 3x3 LINK_MODEL_BASED ROTATION signal

Evaluate_Expression

/EXPRESSION=ROTATION_TRANSPOSE(ROTATION::ORIGINAL::PELVIS_SHIFTED_4x4)

/SIGNAL_TYPES=ROTATION

! /SIGNAL_FOLDER=ORIGINAL

! /SIGNAL_NAMES=

/RESULT_TYPES=ROTATION

! /RESULT_FOLDERS=PROCESSED

/RESULT_NAME=_T

/APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE

;

Pose_Euler2Rotation4x4

This was created for the Shadow segments introduced in 2024.

Create a 4x4 Rotation from the Visual3D pose of a segment, with the translation of the origin represented in any coordinate system, and the orientation defined by Euler angles and the Euler sequence.

POSE_EULER2ROTATION4X4(R_HEEL,0,0,0,123)