About 6 months ago, Fred asked a question on the Chandoo.org Forums: I need idea on a simpler formula
In column A I have the total sum product of C to AU
Line one has all the names.
A2 = (B2*C2)+(D2*E2)+(F2*G2)+(H2*I2)+(J2*K2)+(L2*M2)+…+(AT2*AU2)
A3 = (B3*C3)+(D3*E3)+(F3*G3)+…+(AT3*AU3)
Is there is simpler way by line to do this without clicking each cell on line 2?
I tried Sumproduct but I think I have received a wrong answer during testing.
Hui offered a Sumproduct Formula as a solution
=SUMPRODUCT((B2:AT2) * MOD(COLUMN(B2:AT2) -1, 2), (C2:AU2) * MOD(COLUMN(C2:AU2), 2))
and then followed up with a simpler Sumproduct Formula a day later
=SUMPRODUCT(B2:AT2 * C2:AU2 * (MOD(COLUMN(B2:AT2), 2) =0))
Let’s take a look at this second solution.
Setup the Problem
Copy the numbers 10,20 into alternate Cells A2:U2 or download the example file here: Example File (Excel 97-2010)
Copy this formula into B6: =SUMPRODUCT(B2:U2 * C2:V2 * (MOD(COLUMN(B2:U2), 2)=0))
Pull The Formula Apart
Lets take a look inside this formula and see how it works.
=SUMPRODUCT(B2:U2*C2:V2*(MOD(COLUMN(B2:U2),2)=0))
We can see that in the above formula the main function used in the formula is a Sumproduct Function.
=SUMPRODUCT(B2:U2*C2:V2*(MOD(COLUMN(B2:U2),2)=0))
Within the Sumproduct function there are 3 arrays, which are multiplied together
Array 1: B2:U2
Array 2: C2:V2
Array 3: (MOD(COLUMN(B2:U2),2)=0)
What’s in these arrays?
Array 1 is simply the range from B2:U2
Array 2 is simply the range from C2:V2, note that it is offset from the first array by 1 Column.
This is so that the first value of the Second Array matches the first value of the First Array. That is they are both in position 1 within there respective arrays.
Array 3 is where all the action is.
Enter =(MOD(COLUMN(B2:U2),2)=0) into a cell and press F9
Excel returns: ={TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE}
Lets look at what is happening here
=(MOD(COLUMN(B2:U2),2)=0)
Mod returns the remainder of the first value Column(B2:U2) after dividing it by the second value 2.
Column(B2:U2) returns the Column Number for each cell in the Range B2:U2.
Because this part of the formula is in a Sumproduct formula it is evaluated as an Array Formula and hence it does this for each cell in the range B2:U2, thus returning an Array as the answer.
We can see that if we enter =MOD(COLUMN(B2:U2),2) into a cell and evaluate it with F9
={0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1}
However in this case we want to convert this from an array of Numbers to an array of True/False
A simple addition of an =0 does the trick
=(MOD(COLUMN(B2:U2),2)=0)
Now causes the formula to return: ={TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE}
So How does this go together with the other 2 arrays?
We now have 3 arrays:
Array 1: 10,20,10,20,10,20,10,20,10,20,10,20,10,20,10,20,10,20,10
Array 2: 20,10,20,10,20,10,20,10,20,10,20,10,20,10,20,10,20,10,20
Array 3: TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE
When Multiplying arrays, Excel multiplies the first value of each array and then the second value of each array, etc, effectively doing
={10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True, 20*10*False , 10*20*True}
You can see above that when the 3 arrays are multiplied it will only be the Odd entries in Arrays 1 & 2 which are evaluated by the Sumproduct, as all the even entries are multiplied by False which is equivalent to Zero
So the above evaluates to
={200,0, 200,0, 200,0, 200,0, 200,0, 200,0, 200,0, 200,0, 200,0, 200}
Sumproduct then takes over and adds the values together returning, 2000, the correct answer.
Problem Extension
After solving the problem, Fred decided to add a column between each entry in the data set.
The solution is posted in the forum and is also shown in the example file.
You can work through that formula at your leisure, except to say that it is similar to the solution above.
Alternate Solution
Luke correctly pointed out that the data was poorly arranged and the solution would be much simpler had the data been more logically arranged.
However as an Excel practioner we are often called to solve other peoples dirty work.
HINTS
You will notice that in the solution of this problem I have done a few small things that make solving the problem easier.
Use Smaller Subsets of the Data.
Instead of putting numbers from Columns B to AU as Fred has I have used a set from Column B to U.
This way I can see all the data on one Excel screen without scrolling as well as the formula links and extents when pressing F2 on the cell containing the formula.
Use Simple Numbers
Use numbers that you can manually check. In this example I can easily, manually, check that the answer should be 2000.
Evaluate
Where ever possible, enter sections of a formula in a cell and evaluate its output:
=(MOD(COLUMN(B2:U2),2)=0) and press F9
={TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE}
See how easily we can check that this section is returning the correct values.
OTHER POSTS IN THIS SERIES:
You can learn more how to pull Excel Formulas apart in the following posts:
http://chandoo.org/wp/category/formula-forensics/
The link above, will show you all the posts in this series
WHAT FORMULAS WOULD YOU LIKE EXAMINED?
If you have any formulas you would like explained please feel free to leave a post here or send me an email:
If the formula is already on Chandoo.org or Chandoo.org/Forums, simply send the link to the post and a Comment number if appropriate.
If sending emails please attach an Excel file with the formula and data














28 Responses to “2010 Calendar – Excel Template [Downloads]”
[...] Download and print the calendars today. You can add notes to individual dates or complete … [...] Uni Ego / Free 2010 Calendar – Download and Print Year 2010 Calendar today [...]
Any chance on a 2016 calendar?
Afternoon,
I have one similar calander that I added conditional formatting to so that I could highlight any planned factory holidays. I think i "borrowed" the formula from another calander so I won't post it here.
I also added week numbers to it using the formula =WEEKNUM(MAX(C6:I6)) Where C6:I6 is the range of dates in that give week. It works fine on most of the months but return strange values on other months (Week 6 in October?) I can't see any logic behind why it does this.
Any suggestions for an alternative formula to give the week numbers?
Regards,
William
Hi Chandoo,
I've added a new feature on your spreadsheet.
This control can be useful for all the sheets where you need to check dates.
Cheers
http://cid-69a78592a23a8438.skydrive.live.com/self.aspx/.Public/2010-calendar%5E_Miguel.xls
Hi Chandoo,
Nice calendar.
Till now whichever calendar I saw in Excel, it contained only the outline sheet.
Good to see monthly views and the mini view too.
Liked the mini view much. 🙂
-Nimesh
@William: This weeknum may be because the input dates to max are not properly formatting as excel dates.
Good tip on the conditional formatting and holidays btw...
@Migueal: Now that is super awesome. This is the reason why I love to blog. Readers will always one up me with such cool alternatives. Thank you for sharing this with us.
@Nimesh: You are welcome 🙂
is it possible to get the Notes section on the outline page to display the notes added to the month page for a specific date?
So if you add thing for January 2nd, and then select January 2nd those notes appear on the outline page
@Shish... You can do that using some formula magic. I would not recommend pushing excel to that as outlook / google calendar / icalc etc. do exactly that much more elegantly.
[...] Perpetual Excel Calendar – Free Downloadable Template [...]
Happy christmas to all of you!
This is really awesome. The nicest calender I've seen for Excel. I also like Miguels version of the sheet.
Just one "feature" is missing to me. As I live in Germany - where weeks start on Monday - I'd like to change this. Could someone please give me a hint how to do this?
Thanks in advance
Jörg
Hi Chandoo, I’ve added some new features on your spreadsheet with your permission.
Check it here:
http://cid-6b219f16da7128e3.skydrive.live.com/self.aspx/.Public/Calendar%5E_Pedro.xlsm
Miguel, this calendar is translated to Spanish language.
Jörg, this new approach allows us to start weeks on Monday.
Also it's possible to start weeks on Sunday if you enable Excel macros and push the arrows.
Best Regards,
Pedro.
@Pedro.. superb stuff.. thanks for sharing the file with all of us.
Hi Chandoo, for dates before March 1, 1900 our calendars are wrong.
In Microsoft Excel, DATE, EOMONTH, WEEKDAY functions return an incorrect result between Monday, January 1, 1900 and Wednesday, February 28, 1900.
See this page: http://support.microsoft.com/kb/214326/en-us/
Microsoft Excel incorrectly assumes that the year 1900 is a leap year in all Excel versions.
That's the reason why our calendar versions only work from March, 1, 1900 until December, 31, 9999.
Your comments are welcome.
Pedro.
@Pedro.. Thanks for pointing that out. wow... This reminds me of the Joel Spolsky's first BillG review - http://www.joelonsoftware.com/items/2006/06/16.html (read it, I am sure you would love it.) when Bill out of blue asks about date time implementations for VBA (which Joel is the program manager for...)
Thanks for sharing the URL too... Here is a specially made, chocolate sprinkled, extra fluffy donut for you 🙂
Hi Chandoo, thanks a lot for the donut but I prefer it without chocolate!
Always it's good to know a little history of Excel.
The Joel Spolsky’s last BillG Excel review was about the "Hall of Tortured Souls"
(See this Excel 95 Easter Egg here: http://www.eeggs.com/items/719.html)
Do not miss the humor!
@Chandoo.. I just return with a new calendar version.
http://cid-6b219f16da7128e3.skydrive.live.com/self.aspx/.Public/calendar-pedrowave.xltx
It helped me to practice conditional formatting, formulas to show check boxes, data validation drop down list, find out Thanksgiving Day's date for any year, how to find dates of public holidays using Excel, all reading your wonderful posts!
Perpetual Calendar Spanish version starting weeks on Monday:
http://cid-6b219f16da7128e3.skydrive.live.com/self.aspx/.Public/calendario-pedrowave.xltx
Main characteristics:
- Not macros.
- Select a year from 1900 to 9999 with a dropdown listbox.
- All date fields with the real date format.
- Easy language change of day of the week and month names because are also dates.
- Hide Saturdays and/or Sundays.
- Week starting on Sunday or Monday.
- Week and month numbers.
- Hyperlink between sheets.
- Consistent colors to Holidays, Diary and Events dates.
- Easy change of Holidays by country.
- Include 80 World Days and you can add more.
- A diary with my birthday and 50 more programable appointments.
- Check box to hide individual dates or all.
- Holidays, diary and events text are showed on each month's sheet.
- Ranges defined with Name Manager variables.
I'll appreciate if you make me some suggestions to improve this calendar.
Pedro.
Please, I need help!
I like all calendar from Pedro, thank you for them. Let me show my problem:
I have 2 excel cells (for example AE12 and AE13) which mean the starting and the ending date of my duty. I need a macro to insert sheets with label YEAR. MONTH (for example 2010. August or similar) with the proper datas between the two dates. Is it possible?
Thank you for reading me and sorry about my terribel english! 🙂
Hello Pedro,
Thanks so much for the modified calendar template. I love the extra functionality you added. Is there any way you could upload an unlocked version? I wanted to change some of the comments and data validation so I could use it for one of my applications.
As for feedback on potential improvements, with all the additions you made the file runs pretty slow. I'm sure this has to do with all the interconnectivity between the various tabs, but if there is a way to use less memory via more efficient formulas or something else I think this would make it easier to use. I have a brand new computer and with it running alone the response was pretty slow. One of the changes I'm making is changing the order of the months to match my company's fiscal year, so maybe something to automate a change like that could be useful.
Cheers,
Peter
Peter, my calendars are unlocked but you need Excel 2007 and 2010 versions to open them.
Now I return with a new Programmable Task Calendar:
http://cid-6b219f16da7128e3.office.live.com/view.aspx/.Public/Calendario%20de%20Tareas.xlsx
Wath an introductory video here:
http://pedrowave.blogspot.com/2010/10/programmable-task-calendar.html
This new calendar allows to select the start month to match the school and fiscal year.
This is great stuff Chandoo and company
Wanted to know if someone had built something similar
I need to store one Excel Sheet on this calendar that has all the holidays
US Holidays appear in RED
UK Holidays appear in Blue
Meetings appear in Green
Submissions appear in Orange
Is there a way I can store the list in a separate worksheet and all the calendars get updated with this?
Thanks
[...] Calendars: Year 2010 Excel Calendar | Year 2009 Excel [...]
please tell me "how to convert Rs.10000/- in to words through excel formula
[...] is all! http://chandoo.org/wp/2009/12/11/2010-calendar-excel-template-downloads/ See more Templates at http://www.vertex42.com/ Share this:Like this:LikeBe the first to like this [...]
Greetings,
Thanks for this wonderful excel vacation tracker. I notice that the tracker only has three months November, December and January 2015, however, I would like to add the other ten months for 2014. Can you please instruct me on how I can add the other months?
Thanking you in advance.
Hi Chandoo,
Calendar: can this be printed as single sheet 8.5x11 inch per month
kanu
@Kanu
Yes,
You can resize it to fit
WOW! I just searching some of like this, that help me.
Thank you for sharing.