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A comment on From scratch: reverse-mode automatic differentiation (in Python). Parent comment

Re:From scratch: reverse-mode automatic differentiation (in ... by ohsonice on Monday June 15, 2020 @01:35AM (#23524124)
Your first link is not working for me on mobile. Thanks for the clarification though.

Exp(x^2) is a finite composition of a polynomial and an exponential function so from what you posted, it does fall into the Wikipedia definition of elementary function.

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Re:From scratch: reverse-mode automatic differentiation (in ... by brewmarche on Monday June 15, 2020 @04:35AM (#23525171)
The first link of your parent should've been https://mathworld.wolfram.com/Erfi.html

They were arguing that the antiderivative F of f: x ↦ exp(x²) is not elementary, whereas f itself is elementary. But both F and f are well-defined functions, which means that f has an indefinite integral, it just happens to be not elementary.

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Re:From scratch: reverse-mode automatic differentiation (in ... by JadeNB on Monday June 15, 2020 @01:55PM (#23530579)
> The first link of your parent should've been https://mathworld.wolfram.com/Erfi.html

Sometimes Markdown eats following parentheses and sometimes it doesn't, and I've never figured out why. When I first viewed the post it showed me the parenthesis not being eaten, but then it did it anyway when I viewed it from the main page (too late for me to edit). Thanks for fixing it up!

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