Obj_ArchValue

SUMMARY

Obj_ArchValue - Retrieve Value from Archive

SYNTAX

Obj_ArchValue(<pointid>,<Time Object>,<ApplyGroup>);

ARGUMENTS

PointId
Name of the Data Object that's value should be retrieved.
Time Object
Name of the Data Object that defines the point of time for that the value of <pointid> should be read out of the archive.
ApplyGroup
Defines the Apply Group the related graph is bound to.

RETURN VALUE

32 bit - according the value format

DESCRIPTION

Provides the measuring value of a Data Object for a defined point of time.

Usage in VISION:
To the standard display of a graph for the Data Object <Graph_Objekt> which is bound to the Apply Group <ApplyGroup> a vertical ruler should be implemented.
That ruler should be movable along the time axis and the value of the graph at the intercept point of graph and ruler should be displayed on a digital meter.

Implementation:
In the area of the graph a BARGRAPH (as a ruler) is inserted.
The Scaling of the Bar graph is identical to that of the graph.
The Format : Direction = right; Style = line
Indicated gets the <Time_Object>, a for that purpose created System Object. The value for that object is varied by NUMERIC EDIT FIELDs for Date and Time - it represents the position of the ruler.
(For convenience of the user buttons to increment / decrement that value should be added.)
An Digital Meter is inserted, to the category "Variables" the job:
Obj_ArchValue(<Graph_Objekt>,<Time_Object>, <Apply_Group>)
Is bound.
That Digital Meter shows the value of the graph at the intercept point of graph and ruler.

EXAMPLES

Obj_ArchValue(SINUS,CUR_Time,TREND1);

The returned value is that of the Data Object "SINUS" shown in the graph where the Apply Group "Trend1" is bound to at the time defined by "CUR_TIME".

Syntax Notation
[aaa]
aaa is optional (zero or one occurences)
(aaa|bbb)
aaa exclusive or bbb
(aaa)*
aaa may occur indefinitely often or may be omitted
(aaa)+
aaa may occur indefinitely often but at least once
(aaa)m..n
aaa may occur from m to n times