Jun
21
awarded Popular Question
Jun
15
asked Gnome keyring not responding
Jun
9
comment Find $\min \sum_{1\le i\le n} x_i\mathbf{z}^T\mathbf{A}\mathbf{y}_i +\mathbf{b}^T\mathbf{x} +\cdots$
Answered here: scicomp.stackexchange.com/questions/19643/…
Jun
9
comment Regarding Max flow problem ( Ford-Fulkerson Algorithm)
"If i take the path : 1-3-5-6 my flow is $F=3+2=5$": Shouldn't it be $F=3+3=6$?
Jun
5
comment OpenCV sparse matrix: how to get the indices of non-zero elements in a row/column
Good point. But that does not really answer my question :( Maybe such a solution does not exist :(
Jun
5
comment OpenCV sparse matrix: how to get the indices of non-zero elements in a row/column
Hi. Thanks for the answer. But I think in case the total number of nodes is greater than the number of columns, your solution is even worse: your solution iterates over all the nodes while the solution I proposed in the question iterates over one row.
Jun
2
asked OpenCV sparse matrix: how to get the indices of non-zero elements in a row/column
May
31
comment Boot stuck at logo screen after upgrading to 14.10
@ShankhoneerChakrovarty: Unfortunately I didn't, and finally had to reinstall the OS.
May
29
awarded Nice Answer
May
28
revised Find $\min \sum_{1\le i\le n} x_i\mathbf{z}^T\mathbf{A}\mathbf{y}_i +\mathbf{b}^T\mathbf{x} +\cdots$
typo
May
27
comment Why is one of the KKT conditions the same as one of the constraints?
Thanks, @MichaelGrant :D
May
26
comment Why is one of the KKT conditions the same as one of the constraints?
Done. Glad that helped.
May
26
answered Why is one of the KKT conditions the same as one of the constraints?
May
26
comment Constrainted optimization involving logarithms
@NotALoner: if we apply the inequality $\log a + \log b +\log c \le 3\log \frac{a+b+c}{3}$ for the first three terms, then we get a function of $x_4$, which is easy to minimize.
May
26
comment Why is one of the KKT conditions the same as one of the constraints?
(Thus the constraints of the original problem should be added to the KKT conditions because we want to find solutions that satisfy these constraints.)
May
26
comment Why is one of the KKT conditions the same as one of the constraints?
The constraints are part of the KKT conditions, by definition. The idea of KKT conditions (for convex problems) is that: if you solve this system of equations/inequations, independently of the original optimization problem (i.e. forget everything about the original optimization problem: objective function, constraints, etc...), then the obtained solutions are the solutions to the primal and dual of the original optimization problem.
May
26
comment Constrainted optimization involving logarithms
There is a simple solution I think: $\log a + \log b \le 2\log \frac{a+b}{2}$.
May
26
comment Why is one of the KKT conditions the same as one of the constraints?
$\alpha_i$ are the dual variables corresponding to the INEQUALITY constraints, thus non-negative. You might want to learn more about Duality Theory (stanford.edu/~boyd/cvxbook, Chapter 5).
May
22
accepted Find $\min \sum_{1\le i\le n} x_i\mathbf{z}^T\mathbf{A}\mathbf{y}_i +\mathbf{b}^T\mathbf{x} +\cdots$
May
22
comment Find $\min \sum_{1\le i\le n} x_i\mathbf{z}^T\mathbf{A}\mathbf{y}_i +\mathbf{b}^T\mathbf{x} +\cdots$
@jf328: Thanks :D
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