Hello all you helpful people, how do i reverse log on excel? i just logged
(LOG) some large numbers for a standard curve, and need to extrapolate back,
now i have logged numbers. how can i do this on excel? i can do it on a
calculator!
Thanks
Charli

=10^A1

or

=POWER(10,A1)

This is what Berard Liengme answered to a similar question:

----------------
If LOG(y) = x; then y = 10^x.
That is the definition of logarithm
So the 'antilog' is 10^x to get y

If you are using logs to bas e (natural logs), then use EXP(x) to find y.
Have a look at you hand calculator and you will see the same relationships
----------------


--
Kind regards,

Niek Otten
Microsoft MVP - Excel


"Charli B" <Charli wrote in message ...
| Hello all you helpful people, how do i reverse log on excel? i just logged
| (LOG) some large numbers for a standard curve, and need to extrapolate back,
| now i have logged numbers. how can i do this on excel? i can do it on a
| calculator!
| Thanks
| Charli

FOr natural LOGs, use the EXP() function.
--
Gary''s Student - gsnu200795


"Charli B" wrote:

Hello all you helpful people, how do i reverse log on excel? i just logged
(LOG) some large numbers for a standard curve, and need to extrapolate back,
now i have logged numbers. how can i do this on excel? i can do it on a
calculator!
Thanks
Charli

Here is exactly what i did:
=LOG(66500)
=LOG(55600)
=LOG(42700)
=LOG(34600)
=LOG(27000)
=LOG(20000)
=LOG(14300)
=LOG(6500)
This gave me:
4.822821645
4.745074792
4.630427875
4.539076099
4.431363764
4.301029996
4.155336037
3.812913357
i used these as part of a standard curve. the trend line gave me a formula,
which i used on some unknowns. this gave me:4.240522549, 4.280013725 and
4.214195098. i need to get these back to the large numbers like the ones i
started with. EXP() gives me too small a number.
Thanks
Charli



"Gary''s Student" wrote:

FOr natural LOGs, use the EXP() function.
--
Gary''s Student - gsnu200795


"Charli B" wrote:

Hello all you helpful people, how do i reverse log on excel? i just logged
(LOG) some large numbers for a standard curve, and need to extrapolate back,
now i have logged numbers. how can i do this on excel? i can do it on a
calculator!
Thanks
Charli

You are using log based 10. To invert use:

=10^4.240522549
displays: 17398.93033

--
Gary''s Student - gsnu200795


"Charli B" wrote:

Here is exactly what i did:
=LOG(66500)
=LOG(55600)
=LOG(42700)
=LOG(34600)
=LOG(27000)
=LOG(20000)
=LOG(14300)
=LOG(6500)
This gave me:
4.822821645
4.745074792
4.630427875
4.539076099
4.431363764
4.301029996
4.155336037
3.812913357
i used these as part of a standard curve. the trend line gave me a formula,
which i used on some unknowns. this gave me:4.240522549, 4.280013725 and
4.214195098. i need to get these back to the large numbers like the ones i
started with. EXP() gives me too small a number.
Thanks
Charli



"Gary''s Student" wrote:

FOr natural LOGs, use the EXP() function.
--
Gary''s Student - gsnu200795


"Charli B" wrote:

Hello all you helpful people, how do i reverse log on excel? i just logged
(LOG) some large numbers for a standard curve, and need to extrapolate back,
now i have logged numbers. how can i do this on excel? i can do it on a
calculator!
Thanks
Charli