5.6.9 XVType
This structure defines a physical value relative to a X axis and it is used as the DataType of the Value of XYArrayItemType. For details see 5.3.4.3.
Many devices can produce values that can perfectly be represented with a float IEEE 32 bits but, they can position them on the X axis with an accuracy that requires double IEEE 64 bits. For example, the peak value in an absorbance spectrum where the amplitude of the peak can be represented by a float IEEE 32 bits, but its frequency position required 10 digits which implies the use of a double IEEE 64 bits.
Its elements are defined in Table 35.
| Name | Type | Description |
|---|---|---|
| XVType | structure | |
x | Double | Position on the X axis of this value |
value | Float | The value itself |
Its representation in the AddressSpace is defined in Table 36.
| Attribute | Value | |||||
| BrowseName | XVType | |||||
| IsAbstract | False | |||||
| References | NodeClass | BrowseName | DataType | TypeDefinition | Other | |
|---|---|---|---|---|---|---|
| Subtype of Structure defined in OPC 10000-5. | ||||||
| Conformance Units | ||||||
|---|---|---|---|---|---|---|
| Data Access XYArrayItemType |