I am doing some work in Excel and am running into a bit of a problem. The instruments I am working with save the date and the time of the measurements and I can read this data into Excel with the following format:
A B
1 Date: Time:
2 12/11/12 2:36:25
3 12/12/12 1:46:14
What I am looking to do is find the difference in the two date/time stamps in mins so that I can create a decay curve from the data. So In Excel, I am looking to Make this (if the number of mins in this example is wrong I just calculated it by hand quickly):
A B C
1 Date: Time: Time Elapsed (Minutes)
2 12/11/12 2:36:25 -
3 12/12/12 1:46:14 1436.82
I Have looked around for a bit and found several methods for the difference in time but they always assume that the dates are the same. I exaggerated the time between my measurements some but that roll over of days is what is causing me grief. Any suggestions or hints as to how to go about this would be great. Even If I could find the difference between the date and times in hrs or days in a decimal format, I could just multiple by a constant to get my answer. Please note, I do have experience with programming and Excel but please explain in details. I sometimes get lost in steps.
time and date are both stored as numerical, decimal values (floating point actually). Dates are the whole numbers and time is the decimal part (1/24 = 1 hour, 1/24*1/60 is one minute etc...)
Date-time difference is calculated as:
date2-date1
time2-time1
which will give you the answer in days, now multiply by 24 (hours in day) and then by 60 (minutes in hour) and you are there:
time elapsed = ((date2-date1) + (time2-time1)) * 24 * 60
or
C3 = ((A3-A2)+(B3-B2))*24*60
To add a bit more perspective, Excel stores date and times as serial numbers.
Here is a Reference material to read up.
I would suggest you to use the following:
Combine date to it's time and then do the difference. So it will not cause you any issues of next day or anything.
Please refer to the image with calculations. You may leave your total minutes cell as general or number format.
MS EXCEL Article: Calculate the difference between two times
Example as per this article
Neat way to do this is:
=MOD(end-start,1)*24
where start and end are formatted as "09:00" and "17:00"
Midnight shift
If start and end time are on the same day the MOD function does not affect anything. If the end time crosses midnight, and the end is earlier then start (say you start 23PM and finish 1AM, so result is 2 hours), the MOD function flips the sign of the difference.
Note that this formula calculates the difference between two times (actually two dates) as decimal value. If you want to see the result as time, display the result as time (ctrl+shift+2).
https://exceljet.net/formula/time-difference-in-hours-as-decimal-value
get n day between two dates, by using days360 function =days360(dateA,dateB)
find minute with this formula using timeA as reference =(timeB-$timeA+n*"24:00")*1440
voila you get minutes between two time and dates
I think =TEXT(<cellA> - <cellB>; "[h]:mm:ss") is a more concise answer. This way, you can have your column as a datetime.
Related
I have a problem where I am trying to calculate in Excel if any part of a provided work duty time period is contained within a user defined period which specifies the night working hours e.g. 2330-0559 or 0000-0630.
If I provide a work duty time I want and any part of the duty is within the specified period it needs to be identified. E.g. 2230-0630 duty time is within both examples above.
I can tried a few different solutions and still not got the right way solve it.
Maybe someone can help. I also know that 24:00 in excel is used for midnight at the end of the day and 00:00 is used for midnight starting the day as excel works from 0-1 as part of the day.
=OR(MOD(A5,1)>$E$2,MOD(A5,1)<$F$2)
I would work with the number of minutes as decimal and with it make a valid range from "Duty start time" and "Duty end time".
Check if you can make any sense out of this:
Here the example:
https://drive.google.com/file/d/1O1B76srlY8sYQHsV_TiZVzi-7B_18eSj/view?usp=sharing
Update: Sorry for the lack of explanation. Here I try my best to clarify how I did it.
Conversion
First of all I try to convert any time into minutes, so 00:00 is 0 minutes, 01:00 is 60 minutes, 24:00 (excel shows 00:00) is 1440 minutes, 25:00 (excel shows 01:00) is 1500 minutes.
That conversion I do with CONVERT(E2,"day", "mn"), which does convert from day to minutes.
Range Normalization and inclusion
Now every range has to be normalized, that means the "End" has to be always bigger than "Start". For 00:00 to 06:00 this works fine, but for 22:00 to 06:00 it needs to be tweaked. So if "Start" is bigger than "End" then I add 1440 mins (24 hours) to "End". That I do with IF(A6>B6, 1440,0).
You then need to see if any "Duty range" contains the "Night range". That normally is done with the formula if (DutyEnd > NightStart AND DuttyStart < NightEnd) then TRUE.
Challenge 1
That was the main concept. But then if you try to compare a range like 00:00-06:00 contained in 24:00-06-00 it does not work. And that is because the converted minutes are 0-360 and 1440-1830, they don't contain each other.
In E3 to fix this I cut down 1440 with modulo (MOD()), then MOD(1440, 1440) = 0. So even if you use values like 25:00 or 52:00, they will be cut down to the smallest amount of minutes. E.g. 25:00 (1500 mins) = 1:00 = 60 mins, 52:00 (3120 mins) = 4:00 = 240 mins
Challenge 2
We have yet another challenge, the possible comparisons are as follows:
00:00-06:00 contained in 00:00-06:00 which in minutes is 0-390 contained in 0-390
00:00-06:00 contained in 22:00-06:00 which in minutes is 0-390 contained in 1320-1830
22:00-06:00 contained in 00:00-06:00 which in minutes is 1320-1830 contained in 0-390
These last two will not match. So that is why in the "Contains" column (E.g.: E6) I compare against the "Night criteria" - 1400 and + 1400.
Hope it is a bit clear. Let me know otherwise..
UNDERSTANDING DATE AND TIME IN EXCEL
Dates in excel are stored as INTEGERS. They represent the days since 1900/01/1 with that date being 1.
Time is stored as a decimal which represents a fraction of a day. 24 hours is 1, 0.5 is 12 noon. etc.
In other words, everything to the left of the decimal is date and everything to the right is time.
JUST USING TIME AND CROSSING MIDNIGHT
This is problematic from the view point that early morning times are less than the late times of the previous day. The fact of the matter is that they are larger. In our heads we do the mental math of knowing the are the following day but we ignore the date aspect.
A quick way to rectify this is to add the date to your time. Life will become much easier with the math. You may however not want to add full dates to start and end times. WITH THE ASSUMPTION that start and end times are not more than 24 hours the simple work around is is to add 1 to the end time when the end time is less than the start time. This means its the next day.
It the example date you provided, column C was insert to CORRECT the end time. It did the check of end less than start if so add one using the following formula:
=B6+(B6<=A6)
The part in brackets is a logic check. It either evaluates to TRUE or FALSE. When excel runs a boolean (TRUE or FALSE) through a math operator (not a function like sum) it will convert TRUE to 1 and FALSE to 0.
LENGTH
Straight forward math of C minus A since C is always after you start and is the larger of the two numbers.
=C6-A6
CROSSING MIDNIGHT
Need to be a little careful in your definition of crossing midnight when a start time or end time is exactly midnight. Technically speaking you did not cross it if you start or stop on it. The difference is really < versus <= or > versus >=. I will leave that to you to sort out. For the math I used:
=AND(A6<1,C6>=1)
Though I did not use this column for anything else
START CHECK
=OR(A6>$F$2,A6<$G$2)
END CHECK
=OR(B6>$F$2,B6<$G$2)
ANY TIME CHECK
I broke this into three columns. It can be combined into one but wanted to show the working parts. The first check is to see if the start time is before the night start and that the shift end time was after the night start time. The second check was similar for the the fisrt except you want to know if the start time is before the night end time and the shift end time is after the night end time. For the OR case you want to check to see if ANY of columns F through I are true:
COLUMN H
=AND(A6<=$F$2,C6>$F$2)
COLUMN I
=AND(A6<$G$2+1,C6>$G$2+1)
Note the +1 for night end time. This is to reflect that the end time is actually on the following day.
COLUMN J
=OR(F6,G6,H6,I6)
or
=(F6+G6+H6+I6)>=1
Place the above formulas in row 6 and copy down as needed
Well, I think I'm missing something but let's see if this works for you. To make this work:
All hours must be typed in hh:mm format
Night Criteria End must be on a different day. This means it must be over 00:00 or formulas won't work. If you type something
like start criteria=22:00 and night criteria= 23:50, both times
would be in the same day, so formulas won't work
This formulas only work in periods less than 24 hours. If anytime the different between criterias is over 24 hours, formulas won't work
properly.
Now, I replied your data like this:
The trick here is dealing with times without dates. Dates in Excel are înteger numbers and decimal parts are the hours/minutes/seconds. So to compare properly hours like this, you need to add an integer part.
Let me explain. In Excel, 18:00 would be 0,75. And 06:00 would be 0,25. If you try to get the difference between both times, you will get -0,5. In decimal it makes sense, but when trying to convert to time, it makes no sense for Excel. So, as I said before, the trick here is adding integers (in this case, because 06:00 is lower than 18:00, we would add +1), so Excel would make 1,25 - 0,75 = 0,5. And Excel can convert 0,5 to hours, and it will return exactly 12 hours, the right result.
So knowing this, the trick in formulas for your data is comparing ends with starts and add 1 or 2 to compare then properly with your criteria. That way Excel can figure out if a time is later or sooner than a criteria.
All my formulas are these ones:
LENGHT: =IF(B5<A5;B5+1-A5;B5-A5)
CROSS MIDNIGHT: =IF(Y(B5<A5;B5<>0);TRUE;FALSE)
START BETWEEN CRITERIA: =IF(AND(IF(A5<$E$2;A5+2;1+A5)>=1+$E$2;IF(A5<$E$2;A5+2;1+A5)<=$F$2+2);TRUE;FALSE)
END BETWEEN CRITERIA: =IF(AND(IF(B5<$E$2;B5+2;1+B5)>=1+$E$2;SI(B5<$E$2;B5+2;1+B5)<=$F$2+2);TRUE;FALSE)
ANY PART:=IF(OR(E5=TRUE;F5=TRUE;AND(A5<$E$2;A5+C5>1+$F$2));TRUE;FALSE)
Anyways, I uploaded a file to my Gdrive, in case it may be helpful to download and check the formulas.
This is the best I got. Probably there is a better way, but I hope this can help you, or at least, you can adapt it to your needs.
https://drive.google.com/open?id=1nrZKfyUhED_y6iiPRSUwRf7GhJlBYt-O
I have a date with hours and minutes like 2/3/2019 10:30 am , and I do the following to find the diffence in hours which I already formatted like ( h )
=now() - date
I want to check if the difference is more than 12 ( where I mean 12 hours) to do something.
if(actual difference>12; "hello"; "bye")
But is not checking the actual difference but the serial difference
How can I check the actual difference in hours?
Dates are stored as numbers where the integer part is the number of days since 1899-12-31. The fractional part measures the time within a day. So, 24 * (now() - date) will give you the number of hours elapsed.
NB: the formatting is only a question of display and won't influence what's done by the formulas.
In order to check conditionaly the difference in the hours unit between two times we can do if(hour(actual difference)>12; "hello"; "bye")
We put the function hour() as noted in
https://support.office.com/en-us/article/calculate-the-difference-between-two-times-e1c78778-749b-49a3-b13e-737715505ff6
I'm trying to get the + and - between two times but if the time I am subtracting from is greater than the time I am subtracting it gives me the difference in 24 hours.
I would like it to show this:
Perhaps this needs to be done in VBA. Have column B be the time to compare to and put max time apart as 12 hours, either positive or negative. So if the time is different by over 12 hours it becomes a negative instead of positive or vise-versa?
#tysonwright that is the best way to do it. Thanks. I assumed there was a better process but apparently there is not. So with that, I change the date to the next day to get 23:59 to 0:01.
If your clockin is in A1 and your Schedule is in A2, your Difference should be:
=IF(A1>B1,TEXT((A1-B1),"-h:mm"),TEXT((B1-A1),"h:mm" ))
Is there an Excel function to calculate the difference between two times? I can't find anything that would work if the first time is yesterday or less than the second time.
Times in Excel for Windows are represented as a fractional number of days from the beginning of January 1st, 1900. To compute the difference between two times or dates, all you have to do is subtract the two. You can then multiply the result to convert from days into the units you want. (ie: *24 to get hours, *1440 to get minutes, *86400 to get seconds, etc.)
Technically speaking, older versions of Excel for the Mac defaulted to the 1904 date system, which used January 1st, 1904 as the first day. The 1904 date system can be enabled even in Windows Excel using a setting in the advanced tab of the Excel options dialog. (Right next door to Lotus 1-2-3 compatibility and DDE configuration.)
This is a good article that quickly explains how excel deals with times regarding a difference between two times, and what to do if they fall on either side of midnight.
Difference between two times
The formula given is =MOD((end_time - start_time)+1,1)
There's a follow up on how to convert times into decimal
How to convert times into hours, minutes or seconds (decimal)
Elegant way to do this is:
=MOD(finish-start,1)*24
If start and finish time are on the same day the MOD function does not change anything.
If time crosses midnight and finish is earlier then start, the MOD function flips the sign of the difference.
Note that this formula calculates the difference between two times (actually two dates) as decimal value. You should display the result as time.
https://exceljet.net/formula/time-difference-in-hours-as-decimal-value
I I'm have small headache caused today by excel and the way it takes control of everything. I have two time values I need to add together then divide by a value I got charged for that time to work out how much it cost me an hour.
so say I was charged day on for 12:30:00
on day 2 I was charged for 13:20:00
and day 3 I was charged for 20:30:00
In total it cost me £1000
The calculation would be
£1000 / (12:30:00 + 13:20:00 + 20:30:00 = 46:20:00)
I would guess to get the answer I would
1000 / Sum(12:30:00+13:20:00+20:30:00) = price per hour
But it doesn't...
I guess I need some sort of convert function on the time or to divide it by 24 to get hours but I'm stuck
Help would be hugely appreciated!
Excel represents times as fractional days, so your function is actually representing the rate per day.
Assuming your times are in cells A1:A3, you can adjust your function to something like:
1000 / Sum(A1:A3) / 24
which will give you the rate per hour (by my calculations, £21.58/hr).
As others have mentioned, you will need to set the cell to a currency format.
Excel should be performing the calculation correctly, but it is just showing as a time. Format the result cell as "number" instead.
You can use the HOUR and MINUTE functions to get the hour and minute portions of the time values, however as lc mentions, you do need to ensure that the formatting of the cell is set to Number, as it will default to a time.
Assuming you have your hh:mm:ss values running down the page (column A), in the next column put the formula
=(A1-INT(A1))*24
underneath this you can put your formula
= 1000 / SUM(A1:A3)
but don't forget to format it as Number.