Here is an interesting problem to start your day.
Let’s say you work as DNA sequencing engineer at The Enterprise. And you just unlocked the sequence that is responsible for all male problems. The early onset of baldness. The sequence code is AAAA. And you want to find out how many times this sequence is found in a sample of DNA strings, in the range B6:B19. Essentially you want this:
So how do you write the formula?
Counting occurrences using Excel formulas
Let’s say your target to find is in $C$3 and the full sequence is in B6. We can use below formula to find how many times C3 is present in B6.
=(LEN(B6) - LEN(SUBSTITUTE(B6,$C$3,""))/LEN($C$3)
How does this formula work?
Let’s go inside out (said male baldness to the head):
SUBSTITUTE(B6,$C$3,””): This replaces all occurrences of C3 in B6 with empty string.
LEN(SUBSTITUTE(…)): This will return the length of new text after replacing all C3s in B6.
LEN(B6): this simply gives us the length of original text
LEN(B6)-LEN(SUBSTITUTE(…)): Will give us the count of total letters replaced.
(LEN(..)-LEN(..))/LEN($C$3): Tells us how many times C3 is present in B6.
So there you go.
Download Example Workbook:
Click here to download the example workbook. Play with the formulas to learn more.
A challenge for you – Find total occurrence count with single formula:
Let’s say you want to find out how many times $C$3 is present in a range – B6:B19 with one formula. How would you write it?
Please post your answers in comments section.
Check out below examples to learn more.
- Array formula to count maximum text occurrences in a range
- How to count words in a cell using formulas
- How many times a list of values occurs in another list?
- VLOOKUP based on pattern
PS: Thanks to Simran who emailed me this question.
PPS: The writer is not balding. He still sports plenty of pointy hair 🙂