About Defining Prefix and Suffix Values
You can define the prefix and suffix values for a dimension or dimension symbol by specifying the respective values in the Prefix and Suffix fields of the Dimension Text panel, that appears when you click Dimension Text button on the Annotate tab. The stored prefix and suffix values appear before and after the dimension value or dimension symbol in the graphics window. You can edit and store these prefix and suffix values.
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The prefix and suffix values are considered as the part of the @D or @S value and are not listed as additional text in the dimension text box.
If you override the dimension value by specifying @O in the dimension text box or choose the Tolerance Value Only option under the Tolerance tab, the prefix and suffix values in their respective fields are grayed out, and you cannot edit them. The prefix and suffix values do not appear with the dimensions in the graphics window. The text, before and after @O in the text box, appears in the graphics window.
Some dimensions automatically generate the prefix or suffix values. Such automatically generated prefix and suffix values are populated in their respective fields in the Dimension Text panel. For example, when you create a radius dimension, the character R is automatically populated in the Prefix field.
The prefix and suffix values of dimensions created prior to Creo Parametric are retained as it is. However, when the dimension type of such an existing dimension changes to another type, the prefix and suffix values can change. In such cases, the prefix and suffix fields in the Dimension Text panel are automatically updated. For example, if you change a diameter dimension to a radius dimension, or if you redefine a feature in such a way that a linear dimension changes to a diameter dimension, the prefix field is automatically updated.
When you select multiple dimensions, only options that are applicable to all the selected dimensions are available in the Dimension ribbon.
For example, if your selection set contains a diameter dimension and an overridden dimension that has the string @O in the dimension text panel, the prefix and suffix fields are not available for editing. This is because the prefix and suffix fields are not available for editing for overridden dimensions. If you select a diameter dimension and a radius dimension, the prefix and suffix fields are available for editing.
You can use the search tool to find a dimension with a specific prefix or suffix value.