[R] Searching for antilog function

[Heather J. Branton]

Thank you so much for each of your responses. But to make sure I am 
clear (in my own mind), is this correct?

If  x = 2^y
Then  y = log2(x)

Thanks again. I know this is basic.

...heather

Duncan Murdoch wrote:

>On Wed, 24 Nov 2004 12:26:46 -0500, "Heather J. Branton" <hjb at pdq.com>
>wrote :
>
>  
>
>>Dear R-users,
>>
>>I have a basic question about how to determine the antilog of a variable.
>>
>>Say I have some number, x, which is a factor of 2 such that x = 2^y. I 
>>want to figure out what y is, i.e. I am looking for the antilog base 2 of x.
>>
>>I have found log2 in the Reference Manual. But I am struggling how to 
>>get the antilog of that.
>>    
>>
>
>You seem to be confusing log with antilog, but log2(x) and 2^y are
>inverses of each other, i.e.
>
>log2(2^y) equals y
>
>and 
>
>2^log2(x) equals x
>
>(up to rounding error, of course).
>
>Duncan Murdoch
>
>
>  
>

-- 
_______________________________________________________________________
Heather J. Branton                                  Public Data Queries
Data Specialist                                 310 Depot Street, Ste C
734.213.4964 x312                                  Ann Arbor, MI  48104

               U.S. Census Microdata At Your Fingertips
                          http://www.pdq.com