It is the 4th day of Your week @ PHD and we have already posted some excellent array formulas, productivity hacks and other very useful tips.
Must read: part 1 of excel tips shared by readers | part 2 | part 3
Sticky Notes and Memorizing formula Syntax by Teyln
I have a Post-it note stuck near my monitor to help me remember the syntax of the INDEX-MATCH combo function. It says:
=INDEX(range,^,column#)
MATCH(what,where,FALSE)
The caret ^ in the Index function is where the Match function goes.
Find How Much Experience an Employee Has by Rajinikanth
Formula to find the Employee Experience, if the date Format is text like(Wednesday, March 10, 2004) :
Suppose employee joining date is Wednesday, March 10, 2004
Todays date is : =today()
then the formula to find the Employees Experience in the company like(No.of years, Months, Days) :
=((TEXT(DATEDIF(D11,E11,”y”),”0″)&” ” &”Years”)&”,”&(TEXT(DATEDIF(D11,E11,”ym”),”0″)&” ” &”Months”)&”,”&(TEXT(DATEDIF(D11,E11,”md”),”0″)&” ” &”Days”))
PHD’s note: The formula =TEXT((NOW()-E11)&"",”yy ""years"" m ""months"" dd ""days""") also works and is probably much simpler. It is mentioned in the 100 excel tips post.
Macro reduces the blood pressure by Michael
Perhaps it’s an artifact of my profession, or perhaps it’s a bias I formed back in the Lotus days.but I have never been really comfortable with Microsoft’s apparent distrust of recursion. True, non-convergent recursion can induce a migraine, but those “circular reference” alerts are almost as annoying.
So, for quite a while, I’ve had the following bit of VBA included in my Book.xlt/Book.xltm file:
Private Sub Workbook_Open()
Application.Iteration = True
End Sub
Voila! A pet peeve and annoyance resolved.
Thank you
Thanks to everyone for actively participating in the your week @ PHD. Donuts to Vishy, Rajinikanth, Barbara for sharing several tips. It has been very exciting and fun to learn new tricks from you. I hope you had as much fun learning.
Tomorrow we will have a open thread for all of you to chip in with more tips.
Also, Let me know if you want the your week to be a regular feature.
14 Responses to “How many ‘Friday the 13th’s are in this year? [Formula fun + challenge]”
in C3=2016
in C4=3
in C5=1 (the first next year with three Friday the 13ths)
=SMALL(IF(MMULT(--(MOD(DATE(C3+ROW(1:1000),COLUMN(A:L),13),7)=6),ROW(1:12)^0)=C4,C3+ROW(1:1000)),C5)
formula check in the next 1000 years
This will generate a table of counts of Friday the 13th's by year. If I didn't screw it up the next year with three is 2026.
I created a simple parameter table with a start date and end date that I wanted to evaluate. That calculates the number of days and generates a list of those days. Then filter and group. The generation of the list in power query (i.e. without populating a date table in excel) is pretty cool, otherwise this isn't really doing anything than creating a big date and filtering/counting.
let
Source = List.Dates(StartDateAsDate, Days2, #duration(1,0,0,0)),
ConvertDateListToTable = Table.FromList(Source, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
AddDayOfMonthColumn = Table.AddColumn(ConvertDateListToTable, "DayOfMonth", each Date.Day([Column1])),
AddYearColumn = Table.AddColumn(AddDayOfMonthColumn, "Year", each Date.Year([Column1])),
AddDayOfWeekColumn = Table.AddColumn(AddYearColumn, "Day of Week", each Date.DayOfWeek([Column1])),
FilterFriday13 = Table.SelectRows(AddDayOfWeekColumn, each ([DayOfMonth] = 13) and ([Day of Week] = 5)),
Friday13thsByYear = Table.Group(FilterFriday13, {"Year"}, {{"Number of Friday the 13ths!", each Table.RowCount(_), type number}})
in
Friday13thsByYear
With the parameters replaced by values should you want to play along at home. This runs for 20 years starting on 1/1/2016.
let
Source = List.Dates(#date(2016,1,1), 7300, #duration(1,0,0,0)),
ConvertDateListToTable = Table.FromList(Source, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
AddDayOfMonthColumn = Table.AddColumn(ConvertDateListToTable, "DayOfMonth", each Date.Day([Column1])),
AddYearColumn = Table.AddColumn(AddDayOfMonthColumn, "Year", each Date.Year([Column1])),
AddDayOfWeekColumn = Table.AddColumn(AddYearColumn, "Day of Week", each Date.DayOfWeek([Column1])),
FilterFriday13 = Table.SelectRows(AddDayOfWeekColumn, each ([DayOfMonth] = 13) and ([Day of Week] = 5)),
Friday13thsByYear = Table.Group(FilterFriday13, {"Year"}, {{"Number of Friday the 13ths!", each Table.RowCount(_), type number}})
in
Friday13thsByYear
=MATCH(3,MMULT(N(WEEKDAY(DATE(C3+ROW(1:100)-1,COLUMN(A:L),13))=6),1^ROW(1:12)),)+C3-1
It should be pointed out that Alex's solution, unlike some others, has the additional advantage of being non-array. My solution was nearly identical but with -- and SIGN instead of N and 1^.
=C3-1+MATCH(3,MMULT(--(WEEKDAY(DATE(C3-1+ROW(1:25),COLUMN(A:L),13))=6),SIGN(ROW(1:12))),0)
Sub Friday13()
Dim StartDate As Date
Dim EndDate As Date
Dim x As Long
Dim r As Long
Range("C7:C12").ClearContents
StartDate = CDate("01/01/" & Range("C3"))
EndDate = CDate("31/12/" & Range("C3"))
r = 7
For x = StartDate To EndDate
If Day(x) = 13 And Weekday(x, vbMonday) = 5 Then
Cells(r, 3) = Month(x)
r = r + 1
End If
Next
End Sub
Calculate next year with 3 Friday 13th. Good for 100 years different from year entered in cell C3
Sub ThreeFriday13()
Dim StartDate As Date
Dim EndDate As Date
Dim x As Long
Dim WhatYear As Integer
Dim Counter As Integer
Range("E7").ClearContents
StartDate = CDate("01/01/" & Range("C3") + 1)
EndDate = CDate("31/12/" & Range("C3") + 100)
Counter = 0
For x = StartDate To EndDate
If WhatYear Year(x) Then
WhatYear = Year(x)
'Different year so reset counter
Counter = 0
End If
If Day(x) = 13 And Weekday(x, vbMonday) = 5 Then
Counter = Counter + 1
If Counter = 3 Then
WhatYear = Year(x)
Exit For
End If
End If
Next
Range("E7") = WhatYear
End Sub
*RE-POST as not equal did not show earliuer
Calculate next year with 3 Friday 13th. Good for 100 years different from year entered in cell C3
Sub ThreeFriday13()
Dim StartDate As Date
Dim EndDate As Date
Dim x As Long
Dim WhatYear As Integer
Dim Counter As Integer
Range("E7").ClearContents
StartDate = CDate("01/01/" & Range("C3") + 1)
EndDate = CDate("31/12/" & Range("C3") + 100)
Counter = 0
For x = StartDate To EndDate
If WhatYear NE Year(x) Then
WhatYear = Year(x)
'Different year so reset counter
Counter = 0
End If
If Day(x) = 13 And Weekday(x, vbMonday) = 5 Then
Counter = Counter + 1
If Counter = 3 Then
WhatYear = Year(x)
Exit For
End If
End If
Next
Range("E7") = WhatYear
End Sub
earlier*
I've a doubt with using array formula here.
In sample workbook, I tried to replicate the formula again.
=IFERROR(SMALL(IF(WEEKDAY(DATE($C$3,ROW($A$1:$A$12),13))=6,ROW($A$1:$A$12)),$B7),"")
For this I selected C7 to C12, and typed the same formula and pressed ctrl+alt+Enter. But in all cells it is taking $B7 (and not $B7, $B8, $B9.... etc)
and since it is array formula I can't edit individual cell.
Please guide.
Thanks
Hi Chandoo,
Cool stuff. You need to clarify that the answer of 5 represents the 1st month in the year that has a Friday the 13th, and not the number of Fridays the 13th in the year. Subtle, but important difference.
Thanks,
Pablo
I like the MMULT() function far more, but here's how I would have tackled it. It uses an EDATE() base and MODE() over 100 years. I'm assuming that 100 years is enough time to catch the next year with 3 friday 13th's. Array entered, of course.
{=MODE(IFERROR(YEAR(IF((WEEKDAY(EDATE(DATE(C3, 1, 13), ROW(INDIRECT("1:1200"))))=6), EDATE(DATE(C3, 1, 13), ROW(INDIRECT("1:1200"))), "")), ""))}
Finding all the Friday the 13ths in a Year:
=SUMPRODUCT((DAY(ROW(INDIRECT(DATE(C3,1,1)&":"&DATE(C3,12,31))))=13)*(TEXT(ROW(INDIRECT(DATE(C3,1,1)&":"&DATE(C3,12,31))),"ddd")="Fri"))
{=sum(if(day.of.week(DATe($YEAR;{1;2;3;4;5;6;7;8;9;10;11;12};13);1)=6;1;0))}
just list the years