Trouble with MINVERSE

[David D.]

In cells A1 to C3, I'm typing in:

1 4 7
2 5 8
3 6 9

I then select cells A5 to C7 and type
=MINVERSE(A1:C3) , then CTRL-SHIFT-ENTER

and I get
#NUM! #NUM! #NUM!
#NUM! #NUM! #NUM!
#NUM! #NUM! #NUM!

in cells A5 to C7
What am I doing wrong ? Any ideas ?
Thanks in advance.

[Peo Sjoblom]

That means your matrix is not invertable
Check it with MDETERM, if it returns zero
MINVERSE will return #NUM!

--
Regards,

Peo Sjoblom

(No private emails please, for everyone's
benefit keep the discussion in the newsgroup/forum)



"David D." <[email protected]> wrote in message
news:[email protected]...
> In cells A1 to C3, I'm typing in:
>
> 1 4 7
> 2 5 8
> 3 6 9
>
> I then select cells A5 to C7 and type
> =MINVERSE(A1:C3) , then CTRL-SHIFT-ENTER
>
> and I get
> #NUM! #NUM! #NUM!
> #NUM! #NUM! #NUM!
> #NUM! #NUM! #NUM!
>
> in cells A5 to C7
> What am I doing wrong ? Any ideas ?
> Thanks in advance.
>
>
>

[Max]

Don't think you did anything wrong ..

Maybe the original matrix cannot be inverted

If you change A1 to say, 2, it'll return in A5:C7 as

1 -2 1
-2 1 0.67
1 0 -0.67

You could double check by selecting say, A9:C11,
put in the formula bar: =MMULT(A1:C3,A5:C7)
and array-enter with CTRL+SHIFT+ENTER

A9:C11 will return the identity matrix:

1 0 0
0 1 0
0 0 1

--
Rgds
Max
xl 97
---
GMT+8, 1° 22' N 103° 45' E
xdemechanik <at>yahoo<dot>com
----
"David D." <[email protected]> wrote in message
news:[email protected]...
> In cells A1 to C3, I'm typing in:
>
> 1 4 7
> 2 5 8
> 3 6 9
>
> I then select cells A5 to C7 and type
> =MINVERSE(A1:C3) , then CTRL-SHIFT-ENTER
>
> and I get
> #NUM! #NUM! #NUM!
> #NUM! #NUM! #NUM!
> #NUM! #NUM! #NUM!
>
> in cells A5 to C7
> What am I doing wrong ? Any ideas ?
> Thanks in advance.
>
>
>

[Harlan Grove]

"David D." <[email protected]> wrote...
>In cells A1 to C3, I'm typing in:
>
>1 4 7
>2 5 8
>3 6 9
>
>I then select cells A5 to C7 and type
>=MINVERSE(A1:C3) , then CTRL-SHIFT-ENTER
>
>and I get
>#NUM! #NUM! #NUM!
>#NUM! #NUM! #NUM!
>#NUM! #NUM! #NUM!
....

What are you trying to do with MINVERSE? Your matrix is singular.