OFFSET vs MATCH in array formulas

Hi All,

I'm trying to streamline a worksheet by exchanging OFFSET for MATCH.

The sheet calculates a best fit curve by comparing various data after passing through three different models.

Two of the models work fine, but the third is failing.

I currently have this formula

{=MMULT(MINVERSE($J$15:$K$16),MMULT(TRANSPOSE(OFFSET($B$2,$K$1,0):OFFSET($B$2,$L$1,1)),OFFSET($E$2,$K$1,0):OFFSET($E$2,$L$1,0)))}

which I have replaced with this:

{=MMULT(MINVERSE($J$15:$K$16),MMULT(TRANSPOSE(INDEX(ln_Time,$K$1+1):INDEX(Unity,$L$1+1)),INDEX(Buoyancy_loss,$K$1+1):INDEX(Buoyancy_loss,$L$1+1)))}

where the named ranges are

Buoyancy_loss=Regression!$E$2:$E$1000
ln_Time=Regression!$B$2:$B$1000
sqrt_time=Regression!$D$2:$D$1000
unity=Regression!$C$2:$C$1000

However, I'm generating a #NUM error. Can anyone see where I've screwed it up?

Thanks

When I recreate the above it works for me (XL2007 & XL2010) - could you post a sample with the relevant values in place illustrating the error ?

Thanks DO,

This is one sheet from a much larger workbook. The sheet is worked through by a macro (present in the second attachment), so I've pasted values where there are normally references to other sheets.

The original file is around 8MB, I don't think the board will stand that!

I think the issue is down to J15:K16 rather than the larger formula.

In the INDEX approach you've not offset to Unity range

J15:K16
=MMULT(TRANSPOSE(INDEX(ln_Time,$K$1+1):INDEX(Unity,$L$1+1)),INDEX(ln_Time,$K$1+1):INDEX(Unity,$L$1+1))
Confirmed with CTRL + SHIFT + ENTER

Good grief - schoolboy error.

Thank you.