It often happens that an Online Information System sends cases with too many significant figures in result values. For example, this case:

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Shows 3 significant digits in the attribute values both in the case view and in the report.

We can set the precision in decimal places or significant digits to which values are displayed. Significant digits or significant figures refers to the measurement precision or clinical significance of a floating point number and not to how many digits are displayed after the decimal point when number is displayed. Decimal places refers to the number of figures after the decimal point.

Using significant figures

  • We can set a project-wide default for the precision with which results are shown, or
  • We can set the precision for any particular attribute. This will over-ride the project-wide setting, if there is one.

So, for example, we might use a project-wide setting to show results to two significant figures, but choose other attributes that we want displayed as they are.  Formatting options are set in the Attribute Editor. The project-wide format is set from the Options menu. To set the formatting for a particular attribute, select that attribute in the Attribute
Editor, show the ‘Case View Properties’ dialog (View|Attribute display) and then choose the required format.

The formatting options available are:

  • ‘No formatting’ – the attribute values are shown precisely as they were received from the Online Information System
  • Formatting to one, two, three or four significant figures.

The formatting for an attribute applies to the values shown in the case view (in the Knowledge Builder and the Validator) and to values shown in comments. Note: formatting affects only the way values are displayed. The underlying values remain unchanged and apply in rules.

The user can turn off significant figure formatting by selecting no formatting on the Attribute Editor options menu (set default format) and resetting any individual attribute formats back to default.

If a comment contains a variable expression which evaluates to a number, then the value of the expression in the comment is formatted according to the format defined for the first attribute in that expression.

For example, suppose we insert the expression “max x where y > 1.0” into a comment. If the format defined for x is 2 significant figures, then the value for the expression will also be formatted to 2 significant figures.

If you have a more complicated expression, and still want to format it when used in comments, follow the steps below:

  1. Define the expression as a Calculated Value attribute
  2. Set the significant figure format for that attribute, and
  3. Insert your calculated value attribute into the comment, rather than the ‘raw’ expression.