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Three week ago I visited the Newton Excel Bach web site where I spotted the Dynamically Defined Dancing Pendulums NewtonExcelBach.
Having noticed that Doug had done a nice animation in Strand7 (a Finite Element Analysis program) Strand7, I thought “I can do that in Excel” and so I did.
This post will not go through the logic of constructing and animating the pendulums in Excel as I have described that over at Excelhero.com and readers who are interested are encouraged to visit there and explore the techniques used.
During the Pendulum project I came across two sub-projects which I felt are worthy of a post here at Chandoo.org as they are a great demonstration of some basic VBA techniques as well as demonstrating the ability of VBA to quickly simplify repetitive tasks.
Sample files are attached for Excel 97-2003 and Excel 2007/10 users to follow through the examples.
PENDULUM SIDE PROJECTS
The Pendulum project consists of 16 Pendulums. Each Pendulum requires 4 Named Formulas, meaning that the projects needs 64 Named Formulas for the 16 Pendulum, as well as adding 16 Series to the chart.
(The above animated GIF is a very poor representation of the smooth scrolling achieved in the Excel animation)
I thought it would be a great idea to see if these jobs could be automated and hopefully save some time during the process.
The result was 2 simple VBA routines which will be described below:
NAMED FORMULAS
Each Pendulum in the project was based around 4 Named Formulas
Named Formula for each Pendulum
p1Len =’1′!$B$9 The Length is stored on the worksheet.
p1o =OMax*SIN(SQRT(g/p1Len)*t) Current angular position of Pendulum 1 at time t
p1x =p1Len*SIN(p1o)*{0;1} Current orthogonal X position of Pendulum 1 at time t
p1y =-p1Len*COS(p1o)*{0;1} Current orthogonal Y position of Pendulum 1 at time t
The only difference between the formulas for Pendulum 1 and Pendulum 2 etc is the replacement of the names of p1 with p2 in the various Named Formulas and of the associated formulas.
On a worksheet Named Formulas a number of formulas were written which display the Named Formulas as required above. Then a small VBA routine was written which loads the Named Formulas.
How
On the Named Formulas worksheet, I have added two columns of formulas for the various Named Formulas required.
For the Pendulum Length Named Formulas
For the Pendulum Angular Position Named Formulas
For the Pendulum X Position Named Formulas
For the Pendulum Y Position Named Formulas
When the formula above are copied down they adjust for the various pendulums numbered 1 to 16 based on the row numbers.
I then setup a VBA routine, Load_Named_Ranges, shown below which loads the Named Formulas.
To Use
Select some or all of the required Named Formulas from the Name Column. That is the code will only load the Selected Named Formulas, allowing the user to load 1 or 2 Named Formulas, for testing purposes, or all the Named Formulas if you choose.
Then Execute the Load_Named_Ranges subroutine either using the Big Red Button or directly within the VBA Editor.
The following will load Named Formulas p3Len to p7Len.
The Load_Named_Ranges subroutine is shown below:
Sub Load_Named_Ranges() Dim c As Range For Each c In Selection ActiveWorkbook.Names.Add Name:=c.Text, RefersTo:=c.Offset(, 1).Text Next End SubWhat does the code do?
The code:
1. Defines the start and name of the subroutine,
Sub Load_Named_Ranges()
2. Defines a variable c as a Range object,
Dim c As Range
3. It then loops through each cell in the selection and assigns it to the variable ‘c’;
For Each c In Selection
4. It then adds a new Named Formula,extracting the Name from the Text Value of ‘c’ and extracts the formula from the cell directly to the right of cell ‘c’;
ActiveWorkbook.Names.Add Name:=c.Text, RefersTo:=c.Offset(, 1).Text
The Name and Formula (RefersTo) both use the Text of the cell, which is what is displayed.
5. It then loops through each cell in the selection until it has done them all;
Next
6. Defines the end of the subroutine;
End Sub
Lets Test It
To test the subroutine we will first delete all the Named Formulas beginning with “p”
Goto the Formula Ribbon Bar and select Name Manager
Select all the Named Formulas that begin with “P” and press the delete button
Accept any warnings
Try and Run the Pendulum’s
Nothing happens as there are no formulas
Ensure the Pendulum are turned off, as the code is still running behind the scenes.
Now Goto the Named Formulas Page
Select all the Named Formula Names in Name Column; B3:B66
Click the Load Named Formulas, button
Go back to Page 1 and try and run the Pendulums now.
ADD CHART SERIES
The second sub-project was the addition of 16 Chart series to the Chart, 1 for each Pendulum.
Using the logic of the Named Formulas VBA code above, the 16 Chart Series Names, X Values and Y values were developed using formulas on the Add Cht Series worksheet and then loading into a chart using a simple VBA routine.
The Add_Cht_Series subroutine is in the Add Cht Series sheet object in the VBA editor.
How
On the Add Cht Series worksheet, I have added three columns of formulas for the various Named Formulas required.
For the Pendulum Name, X Range and Y Range.
When these formulas are copied down they adjust for the various pendulums numbered 1 to 16.
I have then setup a VBA routine, Add_Chart_Series, shown below which loads the Named Formulas.
To use Select some or all of the required Chart Series from the Pendulum Name column.
Then Execute the Add_Chart_Series subroutine using the big red button.
The Add_Chart_Series subroutine is shown below:
Sub Add_Cht_Series() Dim sNumb As Integer Dim c As Range Worksheets(“1”).ChartObjects(“Chart 5”).Activate For Each c In Worksheets(“Add Cht Series”).Range(“B19:b20”) sNumb = ActiveChart.SeriesCollection.Count + 1 ActiveChart.SeriesCollection.NewSeries ActiveChart.SeriesCollection(sNumb).Name = c.Text ActiveChart.SeriesCollection(sNumb).XValues = c.Offset(, 1).Text ActiveChart.SeriesCollection(sNumb).Values = c.Offset(, 2).Text Next End Sub
What does the code do?
The code:
1. Defines the start and name of the subroutine,
Sub Add_Cht_Series()
2. Defines a variable sNumb as an integer, and a variable c as a Range object
Dim sNumb As Integer Dim c As Range3. It then activates the Chart containing the pendulum
Worksheets(“1”).ChartObjects(“Chart 5”).Activate
4. It then loops through each cell in the Range defined by the Range, in this case B19:B20 and assigns it to the variable ‘c’; You can adjust the Range to suit.
For Each c In Worksheets(“Add Cht Series”).Range(“B19:B20”)
5. It then counts how many existing series are in the chart and sets the next Series Number sNumb to that value + 1.
sNumb = ActiveChart.SeriesCollection.Count + 1
6. The next 4 lines add a new series to the chart and setup the new series Name, X Value and Y Values. The Name, X Value and Y Values are retrieved from the Text of the cell c and the adjacent two cells using a Range Offset modifier
ActiveChart.SeriesCollection.NewSeries ActiveChart.SeriesCollection(sNumb).Name = c.Text ActiveChart.SeriesCollection(sNumb).XValues = c.Offset(, 1).Text ActiveChart.SeriesCollection(sNumb).Values = c.Offset(, 2).Text7. It then loops through each cell in the selection until it has done them all;
Next
8. Define the end of the subroutine;
End Sub
Lets Test It
To test the subroutine we will first delete a few of the Chart Series
Select the Chart
Select two Pendulums noting the series Number of the Bobs eg: 9 & 10
Goto the Add Chart Series Worksheet
Note the Range Corresponding to the 2 missing Pendulum B11:B12
Goto the VBA Editor
Adjust the Line
For Each c In Worksheets(“Add Cht Series”).Range(“B11:B12”)
With your cursor in the Subroutine press F5 once only
Go back to Page 1 and you should now have 2 New Pendulum
Run the Pendulums now.
You will have to manually set the shape of the Bobs to a Circle and size 15 and re-arrange the order of the series to ensure they are in order, but you can practice that manually.
SUMMARY
The post has shown how using some very simple VBA and a bit of lateral thinking to put together some simple tools to simplify 2 common and repetitive tasks.
In the Named Formulas case, the code took less than 2 minutes for me to write and then another 5 minutes to do the formulas for the Named Formulas. I didn’t try but I am sure it would have taken a good 20+ minutes to enter 64 Named Formulas.
Writing this post took much longer than doing the whole Pendulum Project.
Two examples during my working career, where VBA code has been used to save massive amounts of time and money:
In the first case I wrote some code to combine data from several hundred workbooks with varying numbers of sheets up to 30 and differing quantities of data on each sheet, a task that could have taken weeks manually with the included opportunity for errors to be introduced, into a subroutine which took 30 minutes to run and gave a printout of the results including what files, sheets and rows of data were included in the import.
In a second case a Number of Workbooks, a Word template and some VBA code was used to replace a person whose sole job was to manage that data. This job saved the company $50k+ per annum and the task was given to a clerical person who could now do the task in their spare time.
LINKS
Huis Excel Hero Pendulum: http://www.excelhero.com/blog/
Pendulum Physics: http://hyperphysics.phy-astr.gsu.edu/hbase/pend.html
Newton Excel Bach: http://newtonexcelbach.wordpress.com/2011/05/25/dancing-pendulums-2/
What could your simplify by using automation within Excel ?
What could you simplify or speedup using Excel automation?
Let us know in the comments below:
41 Responses to “Calculate Elapsed Time in Excel [Quick Tips]”
Hi Chandoo,
To calculate time lapses in excel I usually use the DATEDIF function. Even though is undocumented by MS there is a great explanation of its use in Chip Pearson's site :
http://www.cpearson.com/excel/datedif.aspx
Is pretty easy to use and has great flexibility.
See you and keep Excelling!!!
Another great article, I will be linking to it on my blog.
Oliver:
Yes, I think that DATEDIFF do it better.
Great post! This a fantastic tutorial on calculating elapsed time in Excel that could be helpful even to a novice user. Keep up the useful tips!
Also, the Office community on Facebook could really benefit from you knowledge! Check it out at http://www.facebook.com/office
Cheers,
Andy
MSFT Office Outreach Team
hi, Chandoo !!!
for elapsed time , we can use this unique formula either for hours, minutes or seconds : NOW()-A1)
but using respective special number formats
for hours : [h] ==> 46553
for minutes : [m] ==>2793212
for seconds : [s] ==> 167592763
We can also use mean duration for years (orbital period of the Earth around the Sun : i-e tropical year) which is : 365.25 days
and mean duration for month : 365.25/12 days
be Excelent !!!!
@Oliver... Thanks for the pointer to datediff(). I will update the post with information about this as well.
@Glen... thanks for the linklove 🙂
@Andy... Welcome. Thanks for telling us about the office community on FB.
@Modeste ... that is very cool. I will remember these formatting codes for an upcoming article on number formatting codes 🙂
Great tip Chandoo! I use the formula to calculate years elapsed all the time. It can seriously help save a ton of time with calculations. Also, NETWORKDAYS is one that helps and can seriously impress a boss. Keep up the great work here!
No problem! I will definitely be directing people with tough Excel questions to your blog. Keep up the great posts!
Andy
MSFT Office Outreach Team
Hi,
always great posts and a good way to start my day
but regarding the elapsed time calculations: have you never noticed that there is a result difference between using =TODAY()-A1 and using =NETWORKDAYS(A1,TODAY())?
try it for A1= a Monday such as 21sep09 and "today" is e.g. a Thursday; you get 3 or 4 respectively as a result, depending on the formula used; this is because formula =networkdays() always includes both the startdate and the end date and not only the time between these 2.
This is easily corrected/compensated bij always adding a -1 to the =networkdays() formula because the majority of us will count startday as day 0 and then the result will be consistent across the different formulas.
However, you then get into trouble if you calculate the networkdays for a date further in the past and where either the start or end date falls in a weekend.
just thought to point this out as to me these formula's are not interchangeable just like that!
have a great day!
Paul
=DATEDIF([DOJ],TODAY(),"Y") & " Y, " & DATEDIF([DOJ],TODAY(),"YM") & " M, " & DATEDIF([DOJ],TODAY(),"MD") & " D"
This will fix your 30 Days problem
I calculated the time diff between two date+ times by subtracting 2 cells & custom formatted it to "d hh:mm" format.
E.g.
Cell A1 04-Jan-12 6:00 PM
Cell A2 05-Jan-12 4:45 PM
Cell A3 0 22:45 (formula: =A1-A2)
Wat shud i do 2 not display the "zero" values i.e. no. of days in this case is zero hence the cell shud display " 22: 45" and not "0: 22: 45".
@Amol
Try the Custom Format code:
[
<1] hh:mm ; [>=1] d “d” hh:mmHi Chandoo,
If possible to compute the interval of time and date in one column.
In column C I would like to compute the total days and hours . What formula ? Please help
Example.
Column A Column B
2/13/12 3:30 AM 2/14/12 12:00 AM
In referenc to Elapsed time in months
To calculate the elapsed time in months, we can use the formula =(NOW()-A1)/30. This returns the value in 30 day months.
I use to apply formula =ROUND((TODAY()-A1)/30,0). Today, I faced a peculiar situation, A1 has date 01-Mar-2009, and today being 01-Mar-2012, it should be 36 months, but it is showing 37 months!!
Any suggestions to avoid such errors?
Regards,
Prasad DN
All I want to do is add up a series of times and receive a reply that gives me a total. What I used to do was subtrace the end time from the start time and format the result as [hh]:mm but this doesn't seem to work anymore. How has Bill Gates confounded me?
@Pete
I use Excel 2010 and it still works
The times must be entered as times in the format hh:mm:ss or hh:mm without seconds
Adding up times is as simple as =Sum(Range) or =Sum(A2:A10)
then using a Custom Number format as you have mentioned [h]:mm
If this isn't working, 2 ideas
1. Check your times are times and not text
2. Can you share your data or file with us?
My hospital tracks times from patient arrival to various procedures or treatments. When those times cross over midnight, the regular formulas (2nd time minus first time) don’t work because the result is negative and Excel (2007) won’t show a negative number in time format.
I couldn’t find a solution here (chandoo.org) but found one elsewhere that worked and it’s very simple. I would like to share it.
Assuming 1st time in A1 (column for patient arrival time) (11:00 PM), and 2nd time in B1 (column for x-ray given) (12:30 AM)). Should be 1:30 elapsed time.
=B1-A1+(B1<A1) [This comparison is the key to the solution.]
=12:30 AM – 11:00 PM + (12:30 AM < 11:00 PM)
=0.0208 – 0.9583 + (True)
=-0.9375 + (1) [This is the key! If it is false, Excel adds 0. If it’s true, Excel adds 1 and that is what corrects the negative number. Now Excel can interpret the number as a time.]
=0.0625
Converted to hh:mm = 1:30
I wrapped this formula inside an IFERROR one to alert my data entry person if she messed up and applied it to lots of different columns and it has worked wonderfully. No more complaints from the data entry person who just plugs in times from medical charts.
Very interesting solution. Thank you so much for sharing it with all of us.
HI,
I am working on a Xl application..
I want to capture time between two clicks.
Ex, in my application during run somewhere I press OK button and then I click Cancel.. I want to measure time between these two clicks... Is it possible??
Pls help on this...
@shashidhar
The answer is Yes
You will have to add an appropriate VBA event to start and stop a timer.
There are techniques which can time to the millisecond so maybe look those up on the net
WOW!!!!!! I truly love your excel time format program! WHOOOO! I am very interested in how the time formats "update" (manually on a physical keyboard) that "updates" the time into its respective decimal time formats, such as:
YYYY.yyyy, HH.hhh, etc...
How do those formulas or equations work if not in Excel mode? Example: TI calculators, Word, or any other computer language programming? Just wanted to see how it works. E-mail me at Ultra64848689Ti@gmail.com.
Thanks again for an EXCELLENT Excel program into decimal time formats!
Here's an idea: how about creating an APP for iOS and Android? Just wanted to point that out. =-D
Regarding the elapsed time in months:
I made this function to determine the time elapsed since a date using the number of days in each respective month. It's a simple subtraction and I think it works very well:((Year Today-Year A1)*12++(Month Today - Month A1)+(Day Today/Days in Month Today)-Days A1/Days in month A1)
Here's the function:
=((YEAR(TODAY())-YEAR(A1))*12)+(MONTH(TODAY())-MONTH(A1))+(DAY(TODAY())/DAY(DATE(YEAR(TODAY()),MONTH(TODAY())+1,0))-DAY(A1)/DAY(DATE(YEAR(A1),MONTH(A1)+1,0)))
Have a Merry Christmas everyone!!
I need the ability to calculate how much progress we have made between two dates and I want to represent that as a percentage.
I am thinking this would be a combination of today, networkdays & dividing the days elapsed vs the total days. Then it should be as easy as formatting my cell. Any help would be greatly appreciated.
@Christian
Your correct
dates are just numbers and so you can use simple math to derive the percentage
=(Date Now-Start Date)/(End date-Start date)
that will give you a number between 0 and 1
which you can format as a %'age
is there a way out to calculate the productivity for an employee
The day start is at 08:00 and day end is 20:00
The start date / time is recorded and end date / time is recorded
I want to calculate the timelapse taking into consideration the day begin and dayend time.
If the work begins and ends the same day, a simple formula b1-a1 would compute the productivity.
But if the process remains incomplete and is carried over to the next day, then timelines to be computed accordingly
to clarify,
if start time of an activity is 03/15/2015 18:00 hrs and end time is 03/16/2015 11:00 hrs, then the resultant formula should be 5 hrs (ie 18:00 to 20:00 hrs on day1 + 08:00 to 11:00 hrs on day2) ie 2+3
please guide.
Venkatesh, try (b1-a1)-0.5
This will subtract the fixed amount of time between shifts, 12 hours. If the time between shifts varies, then you could reference other cells that contain the variables.
Please help. when I use the networking days formula I get a date (2-may-00) I want actual number of days. I managing projects and I need to know how many days have passed since we received a project to the current date. Please help Thanks
@Aria: Just format the cell as general or number. that will fix the problem.
You rock! I looked at 17 other sites and they all did not work. Yours did. Thanks!
Hi folks ...
calculating age in years , months and days
=text(now()-a1,"yy")&" y " &text(now()-a1,"mm")-1 &" m "&text(now()-a1,"dd") & " d"
Hi, the Elapsed time in days [ =TODAY()-A1 ] works great however, if I do not have a date in A1, it shows 42157. Anyway to get it to display 0 or a Null value?
@Dan
=If(A1="",0,TODAY()-A1)
I get #NAME? and the formula does not work.
Hi Chandoo,
This might be a challenge - I am looking to calculate elapsed time between two columns
Start date Complete date
9/9/2015 7:21 10/2/2015 11:01
I need to take into account the following:
1) The employee works 7:00-3:15 pm each day
2) Std Work hours are 7hrs 45 min each day
3) Need to take into account all holidays in between start and end date
4) Work week is Mon through Friday.
Can you help?
Thanks!
Hi, i have a certain name (wilium) in column A and against this name i have 2 option, 1 Done and 2 Inprogress. i want that i count done again wilium and count inprogress against wilium separately. which formula will work for it??
Hi, i have a certain name (wilium) in column A and against this name i have 2 option, 1 Done and 2 Inprogress in column C. i want that i count done again wilium and count inprogress against wilium separately. which formula will work for it??
Year, month, day results for DoB.
The formulas I have found on the net and the datedif function do not work. This is what I came up with using a Microsoft support paper dated April 1997 with some modifications:
IF(OR(A2>$A$1,ISBLANK(A2)),"",IF(YEAR($A$1)=YEAR(A2),0,IF(MONTH($A$1)>=MONTH(A2),YEAR($A$1)-YEAR(A2),YEAR($A$1)-YEAR(A2)-1))&" years "&MONTH($A$1)-MONTH(A2)+IF(AND(MONTH($A$1)<=MONTH(A2),DAY($A$1)<DAY(A2)),11,IF(AND(MONTH($A$1)=DAY(A2)),12,IF(AND(MONTH($A$1)>MONTH(A2),DAY($A$1)=DAY(A2),ABS(DAY($A$1)-DAY(A2)),DAY(EOMONTH(A2,0))-DAY(A2)+DAY($A$1))&" days")
Check it out...
Hi, Augustin
what about :
calculating age in years , months and days
=YEAR(NOW()-DoB)-1900 & " y " & MONTH(NOW()-DoB)-1 & " m " & DAY(NOW()-DoB) & " d"
Hi Chandoo,
I am looking for help with the elapse time formula. I have a recruitment tracking sheet where we track the number of days the positions are opened, and when they are finally closed.
The opened positions will have a running turnaround time (TAT) formula and I am using this formula:
=NETWORKDAYS (start_date, TODAY (), Holidays2018)
Now, without disrupting the running TAT formula, how do I then get the TAT to stop when we have a final end date? All the information below is row:
- start_date --> Cell A
- TODAY () --> cell B
- end_date --> Cell C
Hope you are able to help. Thanks!
Interesting question. Try this:
Thank you for this helpful article. I was trying for days now to figure it out. Now the only issue I have is that if I do not have a value inputed for =TODAY()-[@[Date Precured]] Date Precured then it shows 44055. How can I get it to leave it blank if there is no data? Thanks again!!!