Conditional formatting

[mpezz]

Given a range in column (e.g. containing 1, 1, 1, 2, 2, 3, 3, 3, 4, 4, 4) is there a way to use conditional formatting to alternate colors for the differenet groups of values (that is: 1s in red, 2s in black, 3s in red, etc.)?

 

[Gerald Higgins]

Hi, welcome to the board.

I think it would be quite easy to use CF to make EVEN values black, and ODD numbers red.
Is this what you want ?

 

[mpezz]

Hi.
What I am looking for is a way to format the different groups, with alternate format. Data could be also text (e.g. a,a,a,a,x,x,x,y,y,y,y).
I would like to highlight blocks of contiguous data.

 

[Gerald Higgins]

OK. I'm not sure how to do that with standard CF.
You could use it to apply a colour based on whether the value in the current cell is the same as the one in the previous cell, but that's not quite what you're after.
It would give you something like this
A...black
A...red
A...red
B...black
C...black
C...red

See what I mean ?
Is that any use ?

 

[mikerickson]

You can do this with two format contitions. Select A2 and set these formulas (and formats)

=MOD(SUMPRODUCT(--((INDEX($A:$A,1,1):INDEX($A:$A,ROW(A1),1))<>(INDEX($A:$A,2,1):INDEX($A:$A,ROW(A2),1)))),2)=0

and

=MOD(SUMPRODUCT(--((INDEX($A:$A,1,1):INDEX($A:$A,ROW(A1),1))<>(INDEX($A:$A,2,1):INDEX($A:$A,ROW(A2),1)))),2)=1

Format the colors appropriatly, these formula error in A1, so A1 should have a "natural" format the same as the =0 condition.

 

[mikerickson]

Cleaner formula

=MOD(SUMPRODUCT(--($A$1:INDEX($A:$A,ROW(A1),1))<>($A$2:INDEX($A:$A,ROW(A2),1)))),2)=0

 

[mpezz]

Thanks, this is what I was looking for.

 

[mikerickson]

You could select cell A2 and set these two CF formulas

Condition 1:
=(1=MOD(SUMPRODUCT(--($A$1:$A1<>$A$2:$A2)),2))

Condition 2:
=True

and copy the formatting to the other cells as needed.