Need a better algorithm ( Occurence of time) - excel

Question

The "B" column has occurence of time in it.Like these
A B
X4T00289 8/4/2011 3:12:07 AM
X4T00289 8/4/2011 3:15:07 AM
X4T00289 8/4/2011 3:18:20 AM
X4T00290 8/4/2011 3:12:37 PM
YCE00194 8/8/2011 5:12:17 AM
YCE00194 8/8/2011 5:14:07 AM
YCE00194 8/10/2011 10:12:06 PM
YCE00194 8/10/2011 10:15:16 AM
Z4W00109 8/12/2011 11:12:22 AM
Z4W00109 8/4/2011 11:58:07 AM
Z4W00109 8/4/2011 12:00:07 PM
I have taken a variant and dumped the range in it like these
var = activesheet.range("A1:B4000").value
QUESTION:
The problem is, I have to identify the consequent rows that has same ID in column A and which occured within 5 minutes and highlight them with color.Take a look at first 2 rows, They occured within 5 minutes and column A value is same for both but the 3rd row occurred after 5 minutes when compared to the first row, So that row should be ignored when highlighting .While coming back to the last 2 rows they also occured within 5 minutes, they should be highlghted with color as they occured within5 minutes. I think you got what i wanted to do. Any questions please comment and I will explain it more cleaner way.
MY APPROACH:
This is what i have tried
, I have used splitting some thing like these
temp = split(text," ")
and then compare temp(0) and temp(1) and temp(2) with consequent rows
temp(0) it has year date and month in it
temp(1) it has Time
temp(2) it has AM or PM
if temp(2) and temp(0) are equal for conesequent rows then this piece of code executes
temp_var=split(temp(1),":") again
again temp_var has temp_var(0)=hours temp_var(1)=minutes temp_var=seconds
Now I have to check hours if hours are equal then
I have to check for minutes like
(minutes - next row minutes) <= 5 then color it
This is what I have done.Im not getting any more better ideas to do it. I guess there might be some other easiest way in do it. may be some inbuilt functions which im not aware of So Let me know is this the only better way to do or any other better approach or algorithm to do it? like faster way to do it?Please help me with this

Answer 1

This is the Code you need, if you need any clarification or change comment here
Sub HighlightDiff()
Dim r As Integer
Dim i As Integer
Dim diff As Integer
Dim y As Integer
Dim m As Integer
Dim d As Integer
Dim h As Integer
r = 4000 ' Total No. of rows
For i = 1 To r
If (Trim(Cells(i, 1).Value) = Trim(Cells(i + 1, 1).Value)) Then
'd = Cells(i, 2).Value - Cells(i + 1, 2).Value
y = Year(Sheet1.Cells(i, 2)) - Year(Sheet1.Cells(i + 1, 2))
m = Month(Sheet1.Cells(i, 2)) - Month(Sheet1.Cells(i + 1, 2))
d = Day(Sheet1.Cells(i, 2)) - Day(Sheet1.Cells(i + 1, 2))
'h = Hour(Sheet1.Cells(i, 2)) - Hour(Sheet1.Cells(i + 1, 2))
If ((y + m + d) = 0) Then
diff = (Hour(Sheet1.Cells(i, 2)) * 60 + Minute(Sheet1.Cells(i, 2))) -
(Hour(Sheet1.Cells(i + 1, 2)) * 60 + Minute(Sheet1.Cells(i + 1, 2)))
If (diff > -5 And diff < 5) Then
Range(Cells(i, 1), Cells(i, 2)).Interior.ColorIndex = 3
End If
End If
End If
Next i
End Sub

Answer 2

here is the algorithm:
for each c in col B
minTime = MIN(col b where ref = current ref)
if c-minTime < 5 min then
change background
end if
next c
Note that you can get dateTime difference simply like this:
if range("onecell")-range("anothercell") < #00:05#

Answer 3

First off, it would be good to ensure that your datetime values in column B are formatted correctly. To do this:
Select all values in column B
Now press CTRL + 1
Select Custom and type in dd/mm/yyyy hh:mm:ss AM/PM
Now you can use the following code to loop through all id's in column A and highlight in red which ones have the same id and are within 5 mins of each other:
Sub WithinFiveMinutes()
Dim rngID As Range, id As Range, timeDiff As Long
Set rngID = Range("A1:A11") //Change for your id list e.g. A1:A4000
For Each id In rngID
If id = id.Offset(1, 0) Then
timeDiff = DateDiff("n", CDate(id.Offset(0, 1)), CDate(id.Offset(1, 1))) //"n" gives time difference in minutes...
If timeDiff >= -5 And timeDiff <= 5 Then
Range(id, id.Offset(0, 1)).Interior.ColorIndex = 3
Range(id.Offset(1, 0), id.Offset(1, 1)).Interior.ColorIndex = 3
End If
End If
Next id
End Sub