## Feature #15869

### Add abs to Matrix

**Description**

While I was studying Markov Chain I had to find the maximum absolute value of the Matrix to divide the matrix in numbers from 0 to 1 to be able to make further analysis. Like this:

q = Matrix[ ... ] max = q.to_a.flatten.map { |e| e.abs }.max q = q / max

So this is the first of two features that I would like to contribute.

- Matrix.abs
- Matrix.max

### History

#### Updated by bonafernando (Fernando Wolf Bona) 27 days ago

**Backport**deleted ()*2.4: UNKNOWN, 2.5: UNKNOWN, 2.6: UNKNOWN***Tracker**changed from*Bug*to*Feature*

#### Updated by bonafernando (Fernando Wolf Bona) 27 days ago

bonafernando (Fernando Wolf Bona) wrote:

While I was studying Markov Chain I had to find the maximum absolute value of the Matrix to divide the matrix in numbers from 0 to 1 to be able to make further analysis. Like this:

q = Matrix[ ... ] max = q.to_a.flatten.map { |e| e.abs }.max q = q / maxSo this is the first of two features that I would like to contribute.

- Matrix.abs
- Matrix.max

#### Updated by marcandre (Marc-Andre Lafortune) 27 days ago

**Assignee**set to*marcandre (Marc-Andre Lafortune)*

#### Updated by shevegen (Robert A. Heiler) 27 days ago

Interesting. Not sure if this has to do with Markov Chain per se, but for storing state

through automata (in bioinformatics), hidden markov models are also used. Perhaps

extending Matrix may be beneficial in general (for ruby as a larger ecosystem;

curiously enough, the third most often downloaded gem is diff-lcs, which is probably

useful in a variety of different applications; I came to it indirectly through Hamming

and Levensthein distances).