Problem 47. Extract leading non-zero digit
Benford's Law states that the distribution of leading digits is not random. This is probably because many things grow logarithmically. Extract the leading digit from these vectors.
- 10 --> 1
- 13 --> 1
- 0.3 --> 3
- -4 --> 4
- -5 --> 5
- -0.006 --> 6
Input will be a vector
x = [1 0.3 -2 0.001 -0.0006, 582398, 3020];
Output should be
y = [1 3 2 1 6 5 3];
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Ned Gulley
on 29 May 2012
I added some extra test cases to fail some of the bogus answers.
Iván Quintanar
on 31 Dec 2017
Amazing Law!!!!!!!!!!!!
Luyu Wang
on 6 Jul 2018
I cannot understand the problem.
Brandon
on 26 Jun 2023
Today I learned that 0.3/0.1 = 2.999999999 but 0.3*10=3
Floats always keep things... interesting...
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