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A comment on CS 168: The Modern Algorithmic Toolbox.

Re:CS 168: The Modern Algorithmic Toolbox by buttery101 on Saturday September 10, 2022 @07:42AM (#32789747)
In the lecture note 6 about regularization, section 3.4: the l1 norm of a vector is simply the sum of the absolute values of the coordinates, and hence it is continuous (and linear). I don't think that the l1 norm is linear since |x+y| # |x| + |y|.
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Re:CS 168: The Modern Algorithmic Toolbox by fjkdlsjflkds on Sunday September 11, 2022 @03:39AM (#32797594)
They probably meant that it is positively homogeneous (i.e. |ax|=|a||x|), I would assume, since it's definitely not a linear function.
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Re:CS 168: The Modern Algorithmic Toolbox by the_svd_doctor on Saturday September 10, 2022 @01:21PM (#32792615)
True. Norms are never linear since they cannot be negative.
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Re:CS 168: The Modern Algorithmic Toolbox by political12345 on Saturday September 10, 2022 @09:49AM (#32790613)
agreed.
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