Nope, only takes a range argument.

That's great, thanks Biff!

--
Domenic
http://www.xl-central.com


In article ,
"T. Valko" wrote:

It returns #VALUE! Or is this because the VBA code
is not compatible with my Mac computer?

Nope, only takes a range argument.

COUNTDIFF will take conditionals.

Array entered:

=COUNTDIFF(IF(B2:B65536=2008,A2:A65536),FALSE,FALS E)

Didn't time this but the "eyeball test" says it's still very fast.


--
Biff
Microsoft Excel MVP


"Domenic" wrote in message
...
In addition, it doesn't look like COUNTU accepts a conditional
statement, such as...

=COUNTU(IF(A2:A100="X",B2:B100))

It returns #VALUE! Or is this because the VBA code is not compatible
with my Mac computer?

--
Domenic
http://www.xl-central.com

In article ,
"T. Valko" wrote:

If the OP wants the most efficient method they *should* use the Morefunc
add-in. Not only is it the most efficient method you also get a library
of
useful functions.

I tested the COUNTU function against the COUNTDIFF function (using
Charles
Williams RangeTimer method).

Filled A2:A65536 with =ROW(). 65,535 unique entries. Average calculation
time (5 calculations):

COUNTU(A2:A65536) = 1.42 secs
COUNTDIFF(A2:A65536) = 0.04 secs

Filled A2:A65536 with random numbers from 0 to 100. 101 unique entries.
Average calculation time (5 calculations):

COUNTU(A2:A65536) = 0.38 secs
COUNTDIFF(A2:A65536) = 0.07 secs

--
Biff
Microsoft Excel MVP


"Bernd P" wrote in message
...
Hello,

I suggest NOT to use the SUMPRODUCT divided by COUNTIF approach
(please see entry 3 of my Excel Dont's:
http://www.sulprobil.com/html/excel_don_ts.html
) and NOT to use the Morefunc addin (entry 1 of that same list) but to
take Charles Williams' COUNTU function.

Please find my analysis on this he
http://www.sulprobil.com/html/count_unique.html

Regards,
Bernd