DateDiff ?

[va!n]

I have a little problem to calculate the time different between two days/times. If someone can show me a working way, it would be nice. What i need is something like:

Procedure Diff (sTimeStamp1.s, sTimeStamp2.s) ; sTimeStamp.s = like 1166173200

Result = "x Years, x Months, x Days, x Hours, x Minutes, x Seconds"

thanks.

[Tranquil]

This is difficult to calculate course there are month with 28/30/31 days. How many days do you want to expect in your difference calculation? 31?

And why holding the timevalue in a string?

[Trond]

Code: Select all

DateDifference = DateLate-DateEarly

Code: Select all

Procedure.l YearDiff(Date)
  ProcedureReturn Year(Date)-1970
EndProcedure

Procedure.l MonthDiff(Date)
  ProcedureReturn Month(Date)-1
EndProcedure

Procedure.l DayDiff(Date)
  ProcedureReturn Day(Date)-1
EndProcedure

Debug YearDiff(DateDifference)
Debug MonthDiff(DateDifference)
Debug DayDiff(DateDifference)
Debug Hour(DateDifference)
Debug Minute(DateDifference)
Debug Second(DateDifference)

[netmaestro]

Won't work, Trond, because the pattern of months will rarely line up properly. Take a six-month date difference, the months will always be assumed to be jan-feb-mar-apr-may-june, which will affect the number of days returned. See the error with these dates:

Code: Select all

dateearly = ParseDate("%yyyy/%mm/%dd/%hh:%ii:%ss", "2006/6/01/00:00:00") 
datelate =  Date()

Too many days! Also - leap years counted in the wrong place will throw it off by a whole day for longer differences.

[atnheaderlen]

Date (...) returns the seconds if a date is entered.
If you do that with the beginn-date and end-date and after this subtract the values you get the difference in seconds. It should be easy to get the days/months/years then.

[jear]

This code will return the time difference as string.

Code: Select all

; TimeDiffString : jear Dez 2005 

;#TimeUnits = "Woche|n,Tag|e,Stunde|n,Minute|n,Sekunde|n" 
#TimeUnits = "week|s,day|s,hour|s,minute|s,second|s" 
  
Procedure.s AddTimeUnit(number.l, unit.l) 
  Protected Result.s, sUnit.s 
  If number = 0 : ProcedureReturn "" : EndIf 
  If number < 0 : number * -1 : EndIf 
  sUnit = StringField(#TimeUnits, unit, ",") 
  If number > 1 
    sUnit = RemoveString(sUnit, "|") 
  Else 
    sUnit = StringField(sUnit, 1, "|") 
  EndIf 
  Result + Space(1) + Str(number) + Space(1) + sUnit  
  ProcedureReturn Result 
EndProcedure 

Procedure.s sTimeDiff(Seconds.l) 
  Protected Result.s 
  Protected Weeks.l, Days.l, Hours.l, Minutes.l 
  Weeks   = Seconds / 604800 : Seconds = Seconds % 604800 
  Days    = Seconds / 86400  : Seconds = Seconds % 86400 
  Hours   = Seconds / 3600   : Seconds = Seconds % 3600 
  Minutes = Seconds / 60     : Seconds = Seconds % 60 
  Result = AddTimeUnit(Weeks,1) 
  Result + AddTimeUnit(Days,2)    : Result + AddTimeUnit(Hours,3) 
  Result + AddTimeUnit(Minutes,4) : Result + AddTimeUnit(Seconds,5) 
  ProcedureReturn Result 
EndProcedure 

PastDate.l = ParseDate("%dd.%mm.%yyyy", "20.12.2005 12:00") 
Debug Date() - PastDate 
Debug sTimeDiff(Date() - PastDate) 
Delay(2000) 
Debug PastDate - Date() 
Debug sTimeDiff(PastDate - Date())

[Tranquil]

@jear:

Your routine gives not the correct results that was requested by vain.

Take a look on the Tips&Tricks section:

http://www.purebasic.fr/english/viewtopic.php?t=25085

[Lewis]

You can use the following code to compute the day difference.

Code: Select all

Procedure.l Days(Year.l, Month.l, Day.l) 
  ; CONVERT DATE PARTS TO JULIAN DAY (SERIAL) NUMBER: 
  A.l = (14 - Month.l) / 12 
  Y.l = Year.l + 4800 - A.l 
  M.l = Month.l + (12 * A.l) - 3 
  D.l = Day.l + Int((153 * M.l + 2) / 5) + (365 * Y.l) + Int(Y.l / 4) 
  ProcedureReturn = D.l - Int(Y.l / 100) + Int(Y.l / 400) - 32045 
EndProcedure 

Debug days(2004,3,1) - days(2004,2,28) ; 2004 was a leap year
Debug days(2001,1,1) - days(2000,1,1)  ; 2000 was a leap year
Debug days(1901,1,1) - days(1900,1,1)  ; 1900 was not a leap year
Debug days(2000,1,1) - days(1900,1,1)  ; 24 leap years between centennials
Debug days(2100,1,1) - days(2000,1,1)  ; ... unless least centennial is divisible by 400
Debug days(1908,7,19) - days(756,3,29)

The Debug Output window displays:

• 2
  366
  365
  36524
  36525
  420871

Are the results correct? You can bet your bottom dollar on it!

Now all that remains is for you to do the time (clock) computation (and, if necessary, subtract a day from the day difference computation).

You might also find (the last part of) this thread interesting:

• http://www.purebasic.fr/english/viewtopic.php?t=24559

As a sidenote, you might be wondering why I choose to use Int() in the Days() function. Well, it's because it's easier for me to write those to ensure that I get integer arithmetic than to constantly try to figure out whether PureBasic will automatically apply integer arithmetic to the computation. Not a big deal, I know, but one needs to be constantly on one's toes to avoid inadvertent use of the float library. I asked for it before (early 2006, I believe) and I noticed that others have recently requested the same in the Wishlist sub-forum: PLEASE, PLEASE, PLEASE give us an integer division operator (eg Div).

[dell_jockey]

PLEASE, PLEASE, PLEASE give us an integer division operator (eg Div).

Have you considered using the mod-operator (%) to create a DIV ?

[gnozal]

I used this one in an old project :

Code: Select all

Procedure.l Julian(year.l, month.l, day.l)
  Protected Days.l, yearsBC.l, yearsAD.l
  If month < 3
    month = month + 12
    year = year - 1
  EndIf
  yearsBC = 4714 - 1                              
  yearsAD = year - 1  
  Days = Int((yearsBC + yearsAD) * 365.25)
  Days = Days - (year / 100)
  Days = Days + (year / 400) 
  Days = Days + Int(30.6 * (month - 1) + 0.2)
  ProcedureReturn Days + day
EndProcedure

It seems to pass the Lewis test !

2
366
365
36524
36525
420871

[Lewis]

PLEASE, PLEASE, PLEASE give us an integer division operator (eg Div).

Have you considered using the mod-operator (%) to create a DIV ?

I'm sure you're just dying to enlighten me, so go ahead!

[PB]

>> Have you considered using the mod-operator (%) to create a DIV ?
>
> I'm sure you're just dying to enlighten me, so go ahead!

http://www.purebasic.com/documentation/ ... ables.html

[Lewis]

>> Have you considered using the mod-operator (%) to create a DIV ?
>
> I'm sure you're just dying to enlighten me, so go ahead!

http://www.purebasic.com/documentation/ ... ables.html

What nonsense is this? Why on earth would you think that directing me to the modulo entry in the PureBasic Reference Manual would make me any the wiser?