Which role is verify_datum_reference_frame function?

huangyhg

Yanhua,

This function is used to make sure that the datums that the user has selected make sense.  Datums are used to control degrees of freedom (translation in X, Y, Z, and rotation about X, Y, Z).  The primary datum controls as many degrees of freedom as the datum feature allows.  The secondary datum controls as many of the remaining degrees of freedom as the datum feature allows.  The tertiary datum controls any remaining degrees of freedom.  For example, it would be illogical to select a plane as primary datum and a second parallel plane as a secondary datum.  There would be no degrees of freedom that the secondary datum could constrain that have not already been constrained by the primary datum.  The verify_datum_reference_frame function will return an error code if an illogical combination of datum features has been selected.



Regards,

Don

From: Yanhua HUANG
Sent: Monday, January 14, 2008 3:57 AM
To: Don Turcotte
Cc: Rick Tischler; Porter Bassett
Subject: Which role is verify_datum_reference_frame function?

Don,

Which role is verify_datum_reference_frame function?

// t:\V44B\DIMENS\FEATCTRLFRMUTIL.CPP

  CPCDdatum_reference tempref(m_pPartProgram, NONE,NULL,DAT_RFS,0,0.0,pPrimary,DAT_RFS,pSecondary,DAT_RFS,pTertiary,DAT_RFS,NULL);

  DRF_STATUS status = tempref.verify_datum_reference_frame();

Yanhua Huang yanhua.huang@hexagonmetrology.com