Subscribe via RSS
Toggle Submenu
  1. Categories
  2. Recent
  3. Tags
View Replies (2)

Resolved Time interval overlap in hours

  1. Issue
0
Votes
Undo
  1. Paul Shue
    Paul Shue
  2. PowerBuilder
  3. Monday, 9 April 2018 15:40 PM UTC

How can you determine the overlap in hours between two time intervals?  

time interval 1: (starttime1 and endtime1) and time interval 2:  (starttime2 and endtime2)

What is the overlap between these 2 different intervals.

  1. TIME
PB2017 R2 build 1756 has no REST Client project
Smaller tabpage flaps in PB 2017 R2
Responses (2)
Michael Kramer
Michael Kramer Accepted Answer Pending Moderation
  1. Monday, 9 April 2018 23:28 PM UTC
  2. PowerBuilder
  3. # 1

Hi Paul,

PowerBuilder has no system functions to do time interval calculations. Neither does PFC. I just checked PFC for PB 2017 including the DateTime service.

Basically, you need two functions:

  • CalculateOverlap: returns the overlap[start; stop] between time intervals A[start; stop] and B[start; stop] using DateTime for all Start and Stop points in time
  • HoursAfter: returns the distance between Start and Stop DateTimes measured in hours
  • - OR - mix the two functions into one, e.g. CalculateOverlapHours. and thereby violate the single responsibility pricinple

Notes on prerequisites for calculating such intervals and durations:

  • You must use DateTime instead of Time to avoid issues across midnight and for duration > 24 hours
  • You must decide whether to ignore time zones or how to handle (EX: Convert to UTC)
  • You must decide whether to ignore start/end daylight savings time or how to handle (EX: Convert to UTC)
  • You must decide whether to ignore "leap seconds" or how to handle (EX: Convert to TAI {aka. Atomic Time} instead of UTC)

HTH /Michael

Comment
Matthew Balent
  1. Matthew Balent
  2. Tuesday, 10 April 2018 18:03 PM UTC
When I tackled this issue in a scheduling window I needed to calculate the days between dates and then the difference in the times.



If you use SQL Server you might find the T-SQL date/time difference methods to be of use.



 

  1. Helpful
Michael Kramer
  1. Michael Kramer
  2. Tuesday, 10 April 2018 20:14 PM UTC
I noted an unexpected behavior in PowerBuilder's SecondsAfter function: It truncates to full seconds before calculating difference in seconds.









Start Time

End Time



Actual Duration

​in seconds



SecondsAfter

return value





SecondsAfter return values





10:20:30.000'000

10:20:30.999'999

0.999'999

0





10:20:30.999'999

10:20:31.000'000

0.000'001

1





10:20:30.000'000

10:20:31.999'999

1.999'999

1









You may need a different "truncate" strategy when calculating duration in hours. /Michael

  1. Helpful
Govinda Lopez @Appeon
  1. Govinda Lopez @Appeon
  2. Tuesday, 10 April 2018 22:45 PM UTC
Hi All,



 



Here's some old code snippets that might help: http://nntp-archive.sybase.com/nntp-archive/action/article/%3C385_7D9D14FDB045A211003D16D785256A25.003D16E985256A25@webforums%3E



 



Regards,

  1. Helpful
There are no comments made yet.
mike S
mike S Accepted Answer Pending Moderation
  1. Monday, 9 April 2018 15:46 PM UTC
  2. PowerBuilder
  3. # 2

see: SecondsAfter ( time1, time2 )

then divide the seconds to get  hours

 

Comment
Paul Shue
  1. Paul Shue
  2. Monday, 9 April 2018 17:17 PM UTC
I am seeking a way to calculate the overlap between 2 distinct time intervals:



time interval 1: (starttime1 and endtime1) and time interval 2:  (starttime2 and endtime2)



What is the overlap between these 2 different intervals.



Thanks for you prompt response

  1. Helpful
Kim Berghall
  1. Kim Berghall
  2. Monday, 9 April 2018 18:17 PM UTC
I think you have to take the max of the start times and the min of the end times and then do a diff between those. if the max is less than the min then there is no overlap.

  1. Helpful
There are no comments made yet.
  • Page :
  • 1


There are no replies made for this question yet.
However, you are not allowed to reply to this question.