Diagnosing an Ambiguous Dimension-Driven Cell
The symbology of constrained elements and of the constraint and dimension elements themselves alert you to ambiguities and inconsistencies in the design.
- If a construction or variable is completely defined by constraints or is constant, it is well-constrained and is displayed in solid white.
- If a construction or variable is not completely defined by constraints, it is under-constrained and is displayed dashed in yellow.
- If a constraint is applied to a set of construction that are already well-constrained, it is redundant and is displayed dashed in red.
Valid constraints are displayed as follows:
Constraint | Displayed In |
---|---|
Dimensions | solid white |
Other geometric constraints | solid blue |
Equations | white |
The remaining ambiguity in a design is summed up by a number called " degrees of freedom." Each new construction adds degrees of freedom as follows:
Each valid constraint removes one or more degrees of freedom.
A well-constrained design has zero degrees of freedom and no redundant constraints. All constructions are well-constrained (displayed in white).
If the number of degrees of freedom is not zero, then parts of the design are under-constrained (displayed in yellow).
When a constraint is added, the remaining degrees of freedom are displayed, followed by the message "Over-constrained" if there are any redundant constraints.