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<TITLE>RE: [LCP]Base 2 logarithms</TITLE>
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<P><FONT SIZE=2>> I'm not sure what that method is. Would that be the trial-and-error</FONT>
<BR><FONT SIZE=2>> method?</FONT>
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<P><FONT SIZE=2>It's the iterative method that converges on the solution. I heard</FONT>
<BR><FONT SIZE=2>that it can be generalized for other "good" functions.</FONT>
<BR><FONT SIZE=2>However, I think it relies on the inverse function being cheap to</FONT>
<BR><FONT SIZE=2>compute, but expoential is not cheap to compute, so, even if</FONT>
<BR><FONT SIZE=2>doable, there is probably no speed benefits to it, though you</FONT>
<BR><FONT SIZE=2>can try.</FONT>
<BR><FONT SIZE=2>Basically, you approxiate the solution (say, your approximation</FONT>
<BR><FONT SIZE=2>is log2(l)=x), then you compute e(x)=y, compare y to l, and use</FONT>
<BR><FONT SIZE=2>this to correct your approximation. I can't remember how the</FONT>
<BR><FONT SIZE=2>correction is done, but it probably is function dependant (and</FONT>
<BR><FONT SIZE=2>probably uses the derivatives of the function).</FONT>
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<P><FONT SIZE=2>-- </FONT>
<BR><FONT SIZE=2>Vincent Penquerc'h </FONT>
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