Practicing exponents (http://www.aaamath.com/dec71ix2.htm).. I am into BLAST and have to know what’s the difference between Expectation value 10 and 1E-10? I got an e-val of 1e-148, is it good or bad?

Now, I recalled what we had back in college. 0.00000304 = 3.04*10-6 (6 places).

I will translate E =10 in my head for now 😉 That makes 3.04E-6 an alternative to the previous solutions.

That makes me sort BLAST results like this: 1e-148 is better or worse than 8e-119? 1*10-148 or 8*10-119? I guess it’s about the exponent rather than the number itself (the base..? Can’t remember?)

And for BLAST e-val cutoffs:10 = 1*10^1 = 1e+1
however 1e-5 = 1*10^-5 = 0.00001

Never to forget that the smaller is the most significant

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