Could someone answer 4gb's 11-year-late question? On Tuesday, April 17, 2018 at 11:53:30 PM UTC+3, 4gb...@gmail.com wrote:
> On Monday, September 3, 2007 at 4:38:21 PM UTC-7, Ludmila Koganer wrote: > > Hi, > > I need to subtract two TOD times to find elapsed time. Currently I convert > > the two TOD times with STCKCONV and determine the elaped time individually, > > and then compute the difference. This works. However I thought I could > > optimize the conversion, a little bit and I was wondering why not subtract the > > two TOD times to begin with. > > > > As I understand TOD time is the number of mic seconds elapsed since midnight > > of 1900-01-01. So when I subtract one TOD value from another the duration > > must be in micro seconds. > I'm 11 years late. Shouldn't you clear the low order 12 bits of each TOD value before adding or subtracting them? Those low order bits are not fractions of a microsecond, so including them in the math can produce up to a micro second error. If you add a series of TOD values without clearing the low bits that can add up to real money. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
