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Oct
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revised Choice Problem: choose 5 days in a month, consecutive days are forbidden
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Oct
4
comment Choice Problem: choose 5 days in a month, consecutive days are forbidden
Thanks, edited :)
Oct
4
answered Choice Problem: choose 5 days in a month, consecutive days are forbidden
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Sep
28
revised How do you integrate imaginary numbers?
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Sep
26
comment Consider the problem minimize $f(x)= x^4 −1. $
The proof of quadratic convergence for Newton's method uses the fact that the first derivative of the function whose zero you are finding (i.e. $f''(x)$ in your case) does not vanish on some interval surrounding the root. But you have $f''(x) = 12x^2$ which is zero at the root $x=0$, so the proof of quadratic convergence fails.
Sep
26
comment Solve linear system with matlab
Also, your text specifies $m\geq n$ but your example has $m < n$ (although I don't think this is relevant - probably just a typo).
Sep
26
comment Solve linear system with matlab
You have more equations than unknowns; why do you expect to be able to find an exact solution?
Sep
11
comment Pseudo Proofs that are intuitively reasonable
@MJD Yes, good to mention the Andreas Blass paper too. I'm not sure whether I knew about it or not when I wrote this answer. If I did, then it was surely an oversight.
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Sep
10
revised Why do we use a Least Squares fit?
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Aug
7
comment Coordinate descent with constraints
Thanks Michael!