Feature #14116
closedAdd Matrix #exponentiate method as Matlab's exp
Description
Add exponentiate method which results in returning a new matrix with each element being an exponent of the number e.
Here is PR for that: https://github.com/ruby/ruby/pull/1762
Updated by greggzst (Grzegorz Jakubiak) over 5 years ago
- Description updated (diff)
Updated by greggzst (Grzegorz Jakubiak) over 5 years ago
- Subject changed from Add Matrix #exponentiate method to Add Matrix #exponentiate method as Matlab's exp
Updated by marcandre (Marc-Andre Lafortune) over 5 years ago
- Status changed from Open to Feedback
- Assignee set to marcandre (Marc-Andre Lafortune)
Thanks for the PR.
The name is not acceptable, as the exponential of a matrix is something different (expm in Matlab): https://en.wikipedia.org/wiki/Matrix_exponential
I wish I was more familiar with machine learning to know how frequent calculating this is. If it is, there should be a name for this, no?
The fact that map{|e| Math.exp(e)}
is quite simple to do makes me even more hesitant to add that method too.
Updated by MSP-Greg (Greg L) over 5 years ago
marcandre (Marc-Andre Lafortune) wrote:
Thanks for the PR.
The name is not acceptable, as the exponential of a matrix is something different
I agree. Not quite a single line method. Maybe something like entrywise_exp
or entrywise_exponential
like in 60860. But as you mentioned, 'is quite simple'...
Updated by shevegen (Robert A. Heiler) over 5 years ago
Once again it is back to the oldest problem in computer technology - giving things a proper name. :-)
Updated by greggzst (Grzegorz Jakubiak) over 5 years ago
marcandre (Marc-Andre Lafortune) wrote:
Thanks for the PR.
The name is not acceptable, as the exponential of a matrix is something different (expm in Matlab): https://en.wikipedia.org/wiki/Matrix_exponential
I wish I was more familiar with machine learning to know how frequent calculating this is. If it is, there should be a name for this, no?
The fact that
map{|e| Math.exp(e)}
is quite simple to do makes me even more hesitant to add that method too.
I changed the name to entrywise_exp as suggested. True about the simplicity but it would be a good shorthand taking into consideration fact that it is used in many cases e.g. multivariate normal distribution.