UDF udfGetElmData() & udfGetElmAuxData()

Prabin Pradhananga_22497

Hi experts, 

I was going through the UDF routines and would like to know the differences between udfGetElmData() and udfGetElmAuxData().

udfGetElmData() (altair.com)

udfGetElmAuxData() (altair.com)

Thanks.

Bill Calver_22424

Hi Prabin,

udfGetElmData() will retrieve data from elements defined by the ELEMENT_SET{} command.  This is the command used by all of our current UI tools to define the 3D elements of a model.  This function should be used in most situations.

udfGetElmAuxData() will retrieve data from auxiliary elements.  This is a lesser used approach to modeling and not generally needed.  It does not refer to auxiliary data.

 

Prabin Pradhananga_22497

Bill Calver_22424 said:

Hi Prabin,

udfGetElmData() will retrieve data from elements defined by the ELEMENT_SET{} command.  This is the command used by all of our current UI tools to define the 3D elements of a model.  This function should be used in most situations.

udfGetElmAuxData() will retrieve data from auxiliary elements.  This is a lesser used approach to modeling and not generally needed.  It does not refer to auxiliary data.

 

Thank you for your response. I exactly want to know from where the data are retrieved. It says quadrature point (obviously not centroid). An element has multiple quadrature point. To which specific quadrature point/points does this data correspond to?

Bill Calver_22424

Hi Prabin,

The function will return the weighted sum across all quadrature points for each element.  The number of quadrature points will depend on the type of element and the specification of quadrature.  For example, full quadrature on a linear tetrahedron is 4 points where reduced quadrature on a linear tetrahedron is only 1 point.  In either case, the function will return one scalar, vector, etc. for each element, not one for each quadrature point.