View Issue Details

IDProjectCategoryView StatusLast Update
000720610000-008: Data AccessSpecpublic2021-09-07 15:14
ReporterJeff Harding Assigned ToKarl Deiretsbacher  
PrioritynormalSeveritymajorReproducibilityN/A
Status closedResolutionfixed 
Summary0007206: ValuePercision is specificed as being a Double but it's description suggests it should be an unsigned int
Description

Is ValuePercision intended to be used only by HMIs to limit the number of decimal places shown or is it intended to also be used programmatically?
Since it is a double what is the expected behavior if it is set to some none positive integer value for example 0.1 or -2.2?

TagsNo tags attached.
Commit Version
Fix Due Date

Activities

Jim Luth

2021-08-24 15:16

administrator   ~0014768

Last edited: 2021-08-24 15:17

Agreed to add clarifying text to Part 8.

  • Should be a whole number.
  • A negative whole number implies precision left of the decimal.
  • non-whole numbers would be rounded as usual.

Needs Errata for 1.03 & 1.04

Jeff Harding

2021-08-24 15:43

developer   ~0014769

Propose we use this text to replace the current descripton of ValuePrecision:

ValuePrecision specifies the maximum precision that the Server can maintain for the item based on restrictions in the target environment.
ValuePrecision can be used for the following DataTypes:
• For Float, Double, and Decimal values it specifies the number of digits after the decimal place when it is a postivie number. It specifies the number digits to the left of the decimal place which are insignificate when it is a negative number. For example a ValuePercision of -2 specifies that the percision of the Value is to the nearest 100. The ValuePercision should always be a whole number and it shall always be interpreted as a whole number by rounding it to the nearest whole number.
• For DateTime values it indicates the minimum time difference in nanoseconds. For example, a ValuePrecision of 20 000 000 defines a precision of 20 ms. The ValuePercision should always be a positive whole number and it shall always be a postive number which is interpreted as a whole number by rounding it to the nearest whole number.
• ValuePrecision can also be used for other subtypes of Double (like Duration) and other Number subtypes that can be represented by a Double.
The ValuePrecision Property is an approximation that is intended to provide guidance to a Client . A Server is expected to silently round any value with more precision that it supports. This implies that a Client may encounter cases where the value read back from a Server differs from the value that it wrote to the Server. This difference shall be no more than the difference suggested by this Property.

Karl Deiretsbacher

2021-09-07 15:13

developer   ~0014819

Changed as suggested in release version 1.05.0.
Also updated Errata for 1.03 and 1.04.

Jim Luth

2021-09-07 15:14

administrator   ~0014820

Agreed to changes in 1.05 and Errata.

Issue History

Date Modified Username Field Change
2021-08-23 14:42 Jeff Harding New Issue
2021-08-23 14:43 Jeff Harding Project 10000-003: Address Space => 10000-008: Data Access
2021-08-23 14:44 Jeff Harding Assigned To => Karl Deiretsbacher
2021-08-23 14:44 Jeff Harding Status new => assigned
2021-08-24 15:16 Jim Luth Note Added: 0014768
2021-08-24 15:17 Jim Luth Note Edited: 0014768
2021-08-24 15:18 Jim Luth Assigned To Karl Deiretsbacher => Jeff Harding
2021-08-24 15:43 Jeff Harding Note Added: 0014769
2021-08-24 15:43 Jeff Harding Status assigned => acknowledged
2021-08-24 15:43 Jeff Harding Assigned To Jeff Harding => Karl Deiretsbacher
2021-08-24 15:43 Jeff Harding Assigned To Karl Deiretsbacher => Jeff Harding
2021-08-24 15:43 Jeff Harding Assigned To Jeff Harding => Karl Deiretsbacher
2021-09-07 15:13 Karl Deiretsbacher Status acknowledged => resolved
2021-09-07 15:13 Karl Deiretsbacher Resolution open => fixed
2021-09-07 15:13 Karl Deiretsbacher Note Added: 0014819
2021-09-07 15:14 Jim Luth Status resolved => closed
2021-09-07 15:14 Jim Luth Note Added: 0014820