Re: log to arbitrary base

[Alexander Hansen]

> On Aug 17, 2015, at 15:23, Eric Smith <address@hidden> wrote:
> 
> Hi
> 
> Both qalc (1) and Matlab have a log function like;
>  log(125, 5) = 3
> 
> How do I find the log to base n with Octave?
> 
> Eric
> 
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y=log(x)/log(n) is a standard technique to do that, and is independent of the 
base of the “log” function.  For example, if you wanted the log of 27 to the 
base 3:

octave:6> log(27)/log(3) #natural log
ans =  3
octave:7> log2(27)/log2(3) #base 2
ans =  3
octave:8> log10(27)/log10(3) #base 10
ans =  3

--AKH