Represents the "O" entry of the number format dictionary object.

It is an optional entry defined as part of the PDF 1.0 specification.

It contains a string representing a PDF name object.

The PDF specification states that this item assumes a value of "S" if no value has been provided.

This item may take one of the following valid values:.

• S
• P

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 263, page 483.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 268, page 596.

The order flag controls whether the numeric value or the unit label is displayed first. When true the unit comes before the number, as in some currency display conventions.