Type of Property

Model Reference Manual

Design Templates : Design Datasets : Type of Property

Type of Property

The data property can return

•

a real value, or

•

a text string value, or

•

a reference value

and the DDPR expression should evaluate to one of these values. So should the DDDF and VALIDV attributes of any owned VVALUE of the property (DDAT).

Whichever type of value is expected is determined by the pseudo attribute used to access the data property. There are different attributes for each type, and for each of local, template, or current design properties as is described below.

The PTYP attribute of the DDAT element can be set to a WORD value (4-6 uppercase alphabetic characters) to signify the type of data stored or evaluated in the property. For text and reference properties this is not essential information but it may be used by applications using the properties. For example it sometimes might have PTYP set to SPRE.

When the property returns a real value its PTYP attribute is important. It should be set to the type of physical quantity being returned. Its common values are:


NONE	- a pure numeric, not a physical property
DIST	- a Distance or Length property
BORE	- a size of BORE property
DATA or ANY	- any physical property so that any checking for consistency is met and no warning issued.

In addition any standard hashcode for a supported physical quantity (dimension) can be used (MASS, ANGL, TEMP etc.) No checks are made for validity since the PTYP can be used by applications for their own needs. Any WORD not recognised is treated as NONE.

The PTYP can also be set to a generic dimension by setting the attribute to a compound unit value of such a dimension (a value has to be supplied for syntax purposes).

PTYP 1kg.degC-1.m2

The DDPR and DDDF and VALIDValue expressions should all evaluate to a quantity whose dimension is the same or equivalent to the PTYPE

DDPR ( XLEN of OWNER + 500mm)

is suitable for a DDAT whose PTYP is DIST. If the expression evaluates to a pure numeric with no dimension then it is assumed to be in the current units of the PTYP dimension.

Warnings are issued if the PTYP does not match the evaluated physical quantity. This will occur when the PTYP is:

•

•

not a valid dimension when it is taken to be NONE

•

a non matching valid dimension

Warnings are suppressed if PTYP is:

•

•

•

The Property now is a physical quantity and this is persisted in any expression that the property is used in (including RULE type, Catalogue, reverse Polish, and PML2 expressions).

It is transferred to any PML2 variable assigned to the property (!a = !!CE.LDPR.HEIG).

If the dimensions in the expression or function arguments do not match then further warnings will be generated:

Warning: DIMENSION(UNIT) MISMATCH in arithmetic/arguments/assignment or format: ANGL expected but DIST supplied (element DDATA /DDSE2-DDAT2).

1974 to current year. AVEVA Solutions Limited and its subsidiaries. All rights reserved.