# Board index » cppbuilder » TDateTime Fractional Times

## TDateTime Fractional Times

2006-08-04 01:20:28 AM
cppbuilder111
Hello,
I've designed an algorithm / calculations around TDateTime's.
But I'm having some problems with the date Mathematics...
Scenario...
A Car is driving from Point A to Point C,
but stops along the way (Point B)
The amount of time in minutes to get from:
Point A to Point B = 9.69696969696969696969 Minutes
Point B to Point C = 10.3030303030303030301 Minutes
Total Time From Point A to Point C = 20 Minutes
If the Car starts driving from Point A @ 8:00 am, and it
takes 20 minutes to get to Point C (8:20 am) then...
What is the exact time at Point B?
What I do, that I thought worked... was
psuedo code:
PointBDateTime = IncMinute(StartingDateTime, 9)
double = 9.69696969696969 Minutes - 9 minutes =
.696969696969696969
// Change Decimal Portion to Seconds
.696969696969696969 * 60 = 41.8181818181818181 seconds
PointBDateTime = IncSeconds(PointBDateTime, 41)
// Change Decimal Portion to MilliSeconds
double = .81818181818181818 * 60 = 49.090909090909
PointBDateTime = IncMilliSeconds(PointBDateTime, 49)
Is this mucked up?
TIA,
Heinz

## Re:TDateTime Fractional Times

Heinz Ketchup wrote:
##### Quote

// Change Decimal Portion to MilliSeconds
double = .81818181818181818 * 60 = 49.090909090909

You ought to multiply this by 1000 to get the correct number of milli
seconds. One millisecond is afterall 1 thousands of a second.
Success.
Wiljo.

## Re:TDateTime Fractional Times

Wiljo < XXXX@XXXXX.COM >wrote:
##### Quote
Heinz Ketchup wrote:

>
>// Change Decimal Portion to MilliSeconds
>double = .81818181818181818 * 60 = 49.090909090909
>
You ought to multiply this by 1000 to get the correct number of milli
seconds. One millisecond is afterall 1 thousands of a second.

Success.

Wiljo.
Thanks! =)
Would explain why I'm off by one second here and there.
Heing =)

{smallsort}