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bman342 bman342 is offline
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Default Function for missing data in a series?

Even better, thanks!

"Biff" wrote:

Here's another way that returns the missing values in a contiguous block.

Entered as an array using the key combination of CTRL,SHIFT,ENTER (not just
ENTER):

=INDEX(ROW($1:$1000),SMALL(IF(ISNA(MATCH(ROW($1:$1 000),A$1:A$750,0)),ROW($1:$1000)),ROW(A1)))

Copy down umtil you get #NUM! errors meaning all the missing values have
been returned. This method works but can be slow on large data sets. Also
note that due to the use of the ROW function the largest number in the
sequence can be 65,536 (in current versions of Excel).

Biff

"Elkar" wrote in message
...
I'm sure there is a more ellegant way to go about this, but I think this
will
work for you:

Let's say your data is in A1:A750

In a seperate column, enter the formula:

=IF(ISNA(RANK(ROW(),$A$1:$A$1000)),ROW(),"")

Copy down through row 1000

The displayed results should be your missing data.

HTH,
Elkar


"bman342" wrote:

I am collecting a series of data labelled numerically from 1-1000. I need
to
determine which in the series are missing. ie I know I have 750 data
elements
out of 1000, so I know there are 250 missing. But I need to detmine which
specific data elements are missing.

Is there a function, or routine to automate this?

Thx!