Count Unique Duplicates in Two Columns

[dwgnome]

Hi,

I need a one formula solution to compare two columns for duplicates and count the number of matched pairs. Need to ingore blanks. Can have matched numbers or letters. Asterik denotes a blank (empty) cell. Also only consider the first matched pair if there are more than one matched pairs.

Col A Col B
a
b a
* b
c c
d y
x f
f z
f z

In this case I only want to consider a:a, b:b, c:c and f:f, resulting in the count of 4.

Any help would be appreciated

 

[Domenic]

Let's assume that A2:B10 contains the following data...

<TABLE style="WIDTH: 96pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=128><COLGROUP><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; WIDTH: 48pt; HEIGHT: 15pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 width=64>A</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 width=64> </TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>B</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>A</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20> </TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>B</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>C</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>C</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>D</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>Y</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>X</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>F</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>F</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>F</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>F</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>Z</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20>F</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65>Z</TD></TR></TBODY></TABLE>

If the expected result is 4, try the following formula that needs to be confirmed with CONTROL+SHIFT+ENTER...

=SUM(IF(FREQUENCY(IF(MMULT((IF(A2:A10<>"",A2:A10,"#")=TRANSPOSE(IF(B2:B10<>"",B2:B10)))+0,ROW(A2:A10)^0),MATCH(A2:A10,A2:A10,0)),ROW(A2:A10)-ROW(A2)+1),1))

 

[dwgnome]

Domenic,

Well done, it worked perfectly!

Thank you for your valuable assistance. Only wish I could understand what it is doing. I am guessing that the TRANSPOSE function re-aligns the data (psuedo sorting) so that they line up as pairs, but that's just a guess. I will dissect the formula and try to learn more.

Cheers!!

 

[Domenic]

Thank you for your valuable assistance.

You're very welcome!

...I am guessing that the TRANSPOSE function re-aligns the data (psuedo sorting) so that they line up as pairs, but that's just a guess.

Basically, each element in A2:A10 is being compared to the array of values in B2:B10. However, since B2:B10 is transposed, a '9 row by 9 column' array is returned. Here's a simple example. If A2:B6 contains the following data...

<TABLE style="WIDTH: 64pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=86><COLGROUP><COL style="WIDTH: 32pt; mso-width-source: userset; mso-width-alt: 1572" span=2 width=43><TBODY><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; WIDTH: 32pt; HEIGHT: 15pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 height=20 width=43>A</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 32pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 width=43></TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 height=20>B</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63>A</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 height=20></TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63>B</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 height=20>C</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63>C</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63 height=20>D</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl63>Y</TD></TR></TBODY></TABLE>

...A2:A6=TRANSPOSE(B2:B6) returns the following array...

{FALSE,TRUE,FALSE,FALSE,FALSE;FALSE,FALSE,TRUE,FALSE,FALSE;TRUE,FALSE,FALSE,FALSE,FALSE;FALSE,FALSE,FALSE,TRUE,FALSE;FALSE,FALSE,FALSE,FALSE,FALSE}

Or, for a better visual...

<TABLE style="WIDTH: 160pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=215><COLGROUP><COL style="WIDTH: 32pt; mso-width-source: userset; mso-width-alt: 1572" span=5 width=43><TBODY><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; WIDTH: 32pt; HEIGHT: 15pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 width=43 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 32pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 width=43 align=middle>TRUE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 32pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 width=43 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 32pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 width=43 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; WIDTH: 32pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 width=43 align=middle>FALSE</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>TRUE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 align=middle>TRUE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>TRUE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD></TR><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 15pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 height=20 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl65 align=middle>FALSE</TD></TR></TBODY></TABLE>

 

[dwgnome]

Thank you for the explanation. I follow what is going on with the transpose matrix. Pretty keen.

 

[Aladin Akyurek]

What follows resorts to an inner If in the formula for distinct count w.r.t. a single range and appears also to work...

Control+shift+enter:

=SUM(IF(FREQUENCY(IF(A2:A10<>"",
   MATCH(IF(ISNUMBER(MATCH("~"&A2:A10,B2:B10&"",0)),A2:A10,""),
     IF(ISNUMBER(MATCH(A2:A10,B2:B10,0)),A2:A10,""),0)),
   ROW(A2:A10)-ROW(A2)+1),1))-1

 

[dwgnome]

Hi Aladin,

Thank you for bringing your perspective on this. Not sure I understand your short explaination though.

When I tried out your formula, I get a quirky result. The formula does not work when you place A, B, C, D in column A and A, B, C, D in Column B within the range A2:A10 and B2:B10. The result is 3 instead of 4. But if I put in any character not already used in any cell within range below the D in column A, then the formula returns 4.

 

[Aladin Akyurek]

Hi Aladin,

Thank you for bringing your perspective on this. Not sure I understand your short explaination though.

When I tried out your formula, I get a quirky result. The formula does not work when you place A, B, C, D in column A and A, B, C, D in Column B within the range A2:A10 and B2:B10. The result is 3 instead of 4. But if I put in any character not already used in any cell within range below the D in column A, then the formula returns 4.

Yeah, I should have known this: the -1 bit would cause trouble in such cases...

 

[dwgnome]

So, I was wondering is there a fix to your formula? I tried changing the values of the 1's and 0's but to no avail. My understanding of such formulas are a bit limited at this time.

Fortunately I have Domenic's formula that works, but it is nice to see and learn of different approaches. Aladin, Could you post a corrected version?

Thank you.

 

[Domenic]

Maybe...

Insert > Name > Define

Name: Array1

Refers to:

=ISNUMBER(MATCH(IF(ISNUMBER(MATCH($A$2:$A$10,$B$2:$B$10,0)),$A$2:$A$10,"#"),IF(ISNUMBER(MATCH($A$2:$A$10,$B$2:$B$10,0)),$A$2:$A$10),0))

Click Add

Name: Array2

Refers to:

=MATCH(IF(ISNUMBER(MATCH($A$2:$A$10,$B$2:$B$10,0)),$A$2:$A$10,"#"),IF(ISNUMBER(MATCH($A$2:$A$10,$B$2:$B$10,0)),$A$2:$A$10),0)

Click Ok

Then try the following formula, that needs to be confirmed with CONTROL+SHIFT+ENTER...

=SUM(IF(FREQUENCY(IF(Array1,Array2),ROW(A2:A10)-ROW(A2)+1),1))