Yeah you're right, the subdifferential of f(x)=|x| at the origin is the interval... | Hacker News

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		OisinMoran on May 3, 2018 \| parent \| context \| favorite \| on: Differentiable Programming: A Semantics Perspectiv... Yeah you're right, the subdifferential of f(x)=\|x\| at the origin is the interval [−1, 1]. In the fourth paragraph of link [1] in the above post they explain quite well why we can get away with this type of trickery even if it seems wrong.

dataflow on May 3, 2018 [–]

> Yeah you're right, the subdifferential of f(x)=|x| at the origin is the interval [−1, 1].

I'm confused where you're seeing absolute value? I never had absolute value anywhere. The second example I wrote just amounted to y = x.

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