Fastest way to find the largest power of 10 smaller than x
- by peoro
Is there any fast way to find the largest power of 10 smaller than a given number?
I'm using this algorithm, at the moment, but something inside myself dies anytime I see it:
10**( int( math.log10(x) ) ) # python
pow( 10, (int) log10(x) ) // C
I could implement simple log10 and pow functions for my problems with one loop each, but still I'm wondering if there is some bit magic for decimal numbers.