====== Compute Model Based Data ======

=== Compute_Model_Based_Data ===

The command **Compute_Model_Based_Data** will compute a signal using a model's segment, Kinetic_Kinematic data. This is the same functionality as the interactive dialog for model based items. For a detailed description of the types of available functions see the [[Visual3D:Documentation:Visual3D_Signal_Types:LINK_MODEL_BASED_Data_Type#Link_Model_Based_Items|Link Model Based Items List]]. The order of rotation for the Cardan angles can be specified by the axes X, Y, or Z, or it can be specified by the Anatomical Axes ML, AP, or AXIAL.

<code>
Compute_Model_Based_Data
/RESULT_NAME=
/FUNCTION=
/SEGMENT=
! /REFERENCE_SEGMENT=LAB
! /RESOLUTION_COORDINATE_SYSTEM=LAB
! /USE_CARDAN_SEQUENCE=FALSE
! /NORMALIZATION=FALSE
! /NORMALIZATION_METHOD=
! /NORMALIZATION_METRIC=
! /NEGATEX=FALSE
! /NEGATEY=FALSE
! /NEGATEZ=FALSE
! /AXIS1=X
! /AXIS2=Y
! /AXIS3=Z
;
</code>

This command structure is the same regardless of whether the command is in the Pipeline or RECALC Pipeline. When this signal is created, the definition of the model based item is stored automatically in the RECALC pipeline.

{{:Compute_Model_Based_Data.jpg}}

For example, the Right Knee Angle signal could be represented as:

{{:RightKneeAngle2.jpg}}

If the text representation of this signal is opened, the following information will be stored

<code>
Compute_Model_Based_Data
/RESULT_NAME=Right Knee Angle
/FUNCTION=JOINT_ANGLE
/SEGMENT=RSK
/REFERENCE_SEGMENT=RTH
/RESOLUTION_COORDINATE_SYSTEM=
! /USE_CARDAN_SEQUENCE=FALSE
! /NORMALIZATION=FALSE
! /NORMALIZATION_METHOD=FALSE
! /NORMALIZATION_METRIC=
! /NEGATEX=FALSE
! /NEGATEY=FALSE
! /NEGATEZ=FALSE
! /AXIS1=X
! /AXIS2=Y
! /AXIS3=Z
;
</code>

What is notable is that the segments are identified as **RSK** and **RTH**, not **Right Shank** and **Right Thigh** as seen in the dialog.

In other words, it appears that the dialog was created as follows:

{{:RightKneeAngle1.jpg}}

This is because the lower level representations are stored with the standard Visual3D acronyms (e.g. those names that are used under the covers), whereas the interface to Visual3D uses the names that are mapped by the config files.

**Note that the command can be executed from the pipeline, but it isn't possible to execute the RECALC pipeline. This is a quirk of the default structure. The RECALC pipeline is executed by selected the RECALC button on the toolbar or executing the Recalc command in the pipeline.**