RequiredEquations 2D/3D• RequiredEquations is an option for FindSwitchTime that specifies which equations, of a constraint that restrains more than one degree of freedom, are to be retained in seeking the switch time. RequiredEquations should be a two element list; the first element applies to the first set of equations of the TimeSwitch pair, the second element applies to the second set. • Allowable values for each element are the following: an integer, a list of integers (1 through the number of degrees of freedom in the constraint), All, or Sum. • The total number of equations specified must be equal to one plus the number of degrees of freedom constrained by the TimeSwitch. • If All is given, all the constraints in the associated side of the TimeSwitch constraint are included. • Sum takes the sum of all equations in the associated side of the TimeSwitch constraint and uses the sum for a single constraint. • Using the Sum setting can lead to a singularity. • The normal method of specifying RequiredEquations is to specify All for one side and specify a single integer equation number for the other. • The default setting is RequiredEquations>{All, Sum}. • See also: TangentConstraint.
