Elapsed Time Function

[Brian Sheely]

I am trying to write an elapsed time sub that will display the
time since a remembered start time. I have got seconds working
but kind of got stuck on minutes, one thought was to convert
all times to elapsed seconds then do the math to extrapolate
Minutes and hours. I am drawing a blank on how to make this work.

Note: I am not asking any one to write code, I will be more then
happy to get a pseudo code strategy or even a hint on a better
direction.

Thanks
Brian

On a side note.. I am learning PB after years of VB experience.
I just wrote an Excel Macro to pull data out of 10000 or so
unique text files, it took about 45 minutes to run. I think I
will rewrite it in PBCC to output to a comma del text file and
see what the speed diff is. From what I have read here it
should be significantly faster. Since this is something I will
reuse in the future it should be worth it. Also I noticed that quite
a few of my favorite functions I have written in VB copy over and
run in PB without modification. Something that makes me very
Happy
BS


'================
'Start PB Dos Code
'================

'this is a test bas to try out the function and and see what
' it does. Once it works I will copy it to the main bas.

DIM Start AS STRING
DIM x AS INTEGER

Start = TIME$

FOR x = 0 TO 65
CLS
LOCATE 2,1
DispTimeLeft Start, "09:00:00"
SLEEP 1
NEXT x
PRINT "done"

SUB DispTimeLeft(StartTime AS STRING)

DIM CurTime AS STRING
DIM CurHr AS INTEGER
DIM CurMn AS INTEGER
DIM CurSc AS INTEGER

DIM StartHr AS INTEGER
DIM StartMn AS INTEGER
DIM StartSc AS INTEGER

DIM DiffHr AS INTEGER
DIM DiffMn AS INTEGER
DIM DiffSc AS INTEGER

'get current time
CurTime = TIME$

'Parse out Hours, Minutes and Seconds into int's
CurHr = VAL(MID$(CurTime,1,2))
CurMn = VAL(MID$(CurTime,4,2))
CurSc = VAL(MID$(CurTime,7,2))

StartHr = VAL(MID$(StartTime,1,2))
StartMn = VAL(MID$(StartTime,4,2))
StartSc = VAL(MID$(StartTime,7,2))

'Calculates diff of start seconds to current Seconds
IF CurSc>=StartSc THEN
DiffSc = CurSc-StartSc
ELSE
DiffSc = (CurSc+60)-StartSc
END IF

'Calculate diff of start minutes to current minutes
IF CurMn>=StartMn THEN
DiffMn = CurMn-StartMn
ELSE
DiffMn = (CurMn+60)-StartMn
END IF

'NOTE: Not sure how to mix minutes and seconds, not to mention hours

'Display results for now
PRINT "Current = "+TRIM$(STR$(CurHR))+":"+TRIM$(STR$(CurMN))+":"+TRIM$(STR$(CurSC))
PRINT "Start = "+TRIM$(STR$(StartHR))+":"+TRIM$(STR$(StartMN))+":"+TRIM$(STR$(StartSC))
PRINT "Diffrence = "+TRIM$(STR$(DiffHR))+":"+TRIM$(STR$(DiffMN))+":"+TRIM$(STR$(DiffSC))

'Other stuff to come later...

END SUB
'================
'End PB Dos Code
'================


------------------

[Michael Mattias]

File dateunit.bas in samples folder of pb-dos compiler:

=============================================================================
'
'  Date routines for PowerBASIC
'  Copyright (c) 1995-97 by PowerBASIC, Inc.  All Rights Reserved.
'     
...
'  DateMath       -  Add/Subtract days to a given date   
...
   Elapsed        -  Return the number of seconds between two time strings

Lots of other stuff in there, too.

[Mark Hunter]

Integer (or long) variables: n, hours, minutes, seconds.

n = number of elapsed seconds
(Use Timer function instead of Time$.)

hours = n\3600
minutes = (n - hours*3600)\60
seconds = n - hours*3600 - minutes*60

(The backwards slash is integer division.)

[This message has been edited by Mark Hunter (edited May 13, 2006).]

[Michael Torrie]

Something that is shorter mathematically, although probably not more efficient computationally is:

hours = n \ 3600
minutes = (n MOD 3600) \ 60
seconds = n MOD 60


I'm doing this from memory, but I think it works. Minutes is equal to the number of seconds not included in any hour (the modulus) divided by 60, and the seconds is the number of seconds that is not included in any full minute.

------------------




[This message has been edited by Michael Torrie (edited May 13, 2006).]

[Mark Hunter]

Yes, that gives the same result, and it’s easier to see the generalization:

days = n \ 60*60*24
hours = (n Mod 60*60*24) \ 60*60
minutes = (n Mod 60*60) \ 60
seconds = n Mod 60

[Brian Sheely]

Here is what I finally got to work. Note I did not have
access to Dateunit.lib but I did find Mark McDonalds Lib
elsewhere on this site. which provided nSeconds that greatly
simplified my life. Any suggestions to improve the following
code is greatly appreciated.
Thanks for all the Help
Brian

'----------------Start PB Code--------------
$INCLUDE "R:\PB35\DBLIB\ELAPTIME\MLIB\MLIB.inc"

'-----------------------------------
'ElaseTime
'Brian Sheely
'05-15-2006
'Inputs: StartTime = Start time to generate elapsed time from
' EndTime = End time to generate elapsed time from
'Output: PB standard format time string "hh:mm:ss"
'Returns the time elapsed from the start time to the end time.
' uses Mark McDonald's "nSeconds" Function from MLIB located at
' http://www.powerbasic.com/files/pub/pbdos/library/
'-----------------------------------
FUNCTION ElapseTime(StartTime AS STRING, EndTime AS STRING)AS STRING

DIM DiffHr AS LONG
DIM DiffMn AS LONG
DIM DiffSc AS LONG

DIM tempDbl AS DOUBLE

DIM DispHr AS STRING
DIM DispMn AS STRING
DIM DispSc AS STRING

DiffSc = nSeconds(StartTime, EndTime)

tempDbl = DiffSc/60

DiffMn = ParseDblToLong(tempDbl)
DiffSc = DiffSc MOD 60

tempDbl = ABS(DiffMn/60)

DiffHr = ParseDblToLong(tempDbl)
DiffMn = DiffMn MOD 60

IF LEN(TRIM$(STR$(DiffHr))) < 2 THEN
DispHr = "0"+TRIM$(STR$(DiffHr))
ELSE
DispHr = TRIM$(STR$(DiffHr))
END IF

IF LEN(TRIM$(STR$(DiffMn))) < 2 THEN
DispMn = "0"+TRIM$(STR$(DiffMn))
ELSE
DispMn = TRIM$(STR$(DiffMn))
END IF

IF LEN(TRIM$(STR$(DiffSc))) < 2 THEN
DispSc = "0"+TRIM$(STR$(DiffSc))
ELSE
DispSc = TRIM$(STR$(DiffSc))
END IF

FUNCTION = DispHr+":"+DispMn+":"+DispSc

END FUNCTION

'-----------------------------------
'ParseDblToLong
'Brian Sheely
'05-15-2006
'Inputs: DblIn = Double Float
'Output: Long int of DblIn value with everything after the decimal removed
' Used to eliminate rounding errors associated with time string manipulation
'-----------------------------------
FUNCTION ParseDblToLong(DblIn AS DOUBLE) AS LONG

DIM TempStr AS STRING
DIM BuildStr AS STRING
DIM x AS INTEGER

TempStr = TRIM$(STR$(DblIn))

'if the number is small enough, str adds "E-2" as an exponent representation
' Since I want whole numbers unrounded I can safely force the output to a
' zero for this application
IF MID$(tempStr,17,1) = "E" THEN
FUNCTION = 0
EXIT FUNCTION
END IF

BuildStr = ""

'Search for the decimal and discard all numerals after and
' including the decimal
FOR x = 1 TO LEN(TempStr)
IF MID$(TempStr,x,1)<>"." THEN
BuildStr = BuildStr + MID$(TempStr,x,1)
ELSE
EXIT FOR
END IF
NEXT x

FUNCTION = VAL(BuildStr)

END FUNCTION

'-----------------End PB Code----------------

------------------

[Mark Hunter]

Keep it simple. The following is modified from a PBDOS program I once wrote.

Declare Function Normalize(Integer) As String
Declare Function ElapseTime(String, String) As String
 
'test program

Dim a As String, b As String
 
a = "05:12:58"
b = "06:10:40"
 
Cls
Print a
Print b
Print ElapseTime(a, b)
'---------------------------------------------------
 
Function Normalize(n As Integer) As String
 If n < 10 Then
  Function = "0" + Trim$(Str$(n))
 Else
  Function =       Trim$(Str$(n))
 End If
End Function
 
Function ElapseTime(StartTime As String, EndTime As String) As String
 Dim hor0 As Integer, min0 As Integer, sec0 As Integer
 Dim hor1 As Integer, min1 As Integer, sec1 As Integer
 
 hor0 = Val(Mid$(starttime,1,2))
 min0 = Val(Mid$(starttime,4,2))
 sec0 = Val(Mid$(starttime,7,2))
 
 hor1 = Val(Mid$(endtime,  1,2))
 min1 = Val(Mid$(endtime,  4,2))
 sec1 = Val(Mid$(endtime,  7,2))
 
 If hor1 < hor0 Then      'if hours decreased, 
  Incr hor1,24            'assume went over just one day
 End If                   '(or could flag as an error, Function = "")
 
 If min1 < min0 Then      'if minutes decreased,
  Incr min1,60            'borrow 60 minutes from the hours
  Decr hor1
  If hor1 < 0 Then Function = "" :Exit Function   'flag as error
 End If
 
 If sec1 < sec0 Then      'if seconds decreased,
  Incr sec1,60            'borrow 60 seconds from the minutes
  Decr min1
  If min1 < 0 Then Function = "" :Exit Function    'flag as error
 End If
 
 Function = Normalize(hor1 - hor0) + ":" + Normalize(min1 - min0) + ":" + Normalize(sec1 - sec0)
End Function

[This message has been edited by Mark Hunter (edited May 15, 2006).]