CAD tip # 13852:

The example in the following iLogic code rounds all numeric parameters starting with "d" (and not calculated from other parameters) to two decimal places. Metric parameters are assumed.

For Each param As Inventor.Parameter In ThisDoc.Document.ComponentDefinition.Parameters
  If param.Name.StartsWith("d",False) Then 'starts with d
    If param.DrivenBy.Count = 0 Then ' not computed
      If param.Units<>"Text" And param.Units<>"Boolean" Then 'numeric only
        Try
          param.Value = Math.Round(param.Value, 2) 'process, e.g. round to 2 decimals
        Catch
        End Try
      End If
    End If
  End If
Next