Relations Errors
After you add or edit a relation and click OK to exit the Relations dialog box, Creo Parametric checks the validity of relations. If errors are found, Creo Parametric flags the erroneous relations so you can correct them.
Error types detected by Creo Parametric include:
Long line—The characters inside the quotes are considered as characters. The relations line has a limit of 80 characters. If the limit is exceeded, an error informs that the line length of the characters is exceeded.
Long symbol—The characters outside the quotes are considered as symbols. A symbol name has a limit of 31 characters. If the limit is exceeded, an error informs that the line length of the symbol is exceeded.
Relation statement length—The relation statement has a limit of 162 characters for a single line. If the relation line includes more than 162 characters and a space, an error informs that the line is too long.
Parse error—A parse error occurs, for example, if a parameter is not defined.
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Constraint violations are not captured by this error check. If a simultaneous relation fails to converge, a warning appears in the message area. If the system detects a simultaneous relation that is not closed, an error message appears on an empty line after the last relation line.
Avoiding Circular Relations
You may erroneously create a circular relation such as this one:
d0 = d1
d1 = d0
When you sort relations, the sorting utility detects a circular relation and issues a warning. However, the preceding lines can be valid parts of a simultaneous equation.
The next example of a circular relation illustrates how you can erroneously redefine a symbol in the course of entering relations:
d0 = d1

...

d0 = 2*d1
These relations are order-dependent and cannot be sorted. The system issues a warning.