Default Constructor for an unlimited variable
{}
constructor for fixed variable
constructor for double bound variable
{ }
constructor for lower bound variable
constructor for upper bound variable
copy constructor
assignment
{ return fFix; }
{ return fBounds || fLowBound || fUpBound; }
{ return fLowBound || fBounds; }
{ return fUpBound || fBounds; }
{ return fLower; }
{ return fUpper; }
internal to external transformation
derivative of the internal to external transformation ( d Int2Ext / d int )
etxernal to internal transformation