Jacob
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 Aug 18 comment Convex optimization approximation @Adam: The problem is fairly simple in $\mathbb{R}^2$ ; is that your goal or are you looking for a general solution? Aug 14 comment Get neighbors for N dimensional square @wonko: It would be more productive if you flagged such posts for moderator attention. Jul 30 comment How to efficiently compute the pareto front in a >2 dimensional multi-objective case? Seems to be a very poorly written paper which only claims to improve the best-case complexity ; I would stick to Kung's algorithm. Aug 28 comment Find the farthest points in d-dimensional space Why were you interested in a $O(n\cdot 2^d)$ algorithm? Aug 19 comment Cartesian Product @DanielFischer: Looks good and easy to understand ; please post as an answer. Jun 2 comment Integer Linear Programming (ILP): NP-hard vs. NP-complete? I see. That decision problem is certainly in NP. But is there a polynomial-time algorithm which can use this decision problem to solve the optimization problem? For example, how do you handle unboundedness, and feasibility? Apr 17 comment Is this a valid way to evaluate a function based on factorials? What would be a better way? Woah. Where do you usually see such functions? Apr 9 comment Matrix calculus : Find the gradient/derivative? $\partial(\operatorname{tr}(Z^T A Z))/\partial X= (A+A^T)X$. Is $A$ symmetric? Apr 8 comment How do I write it as a sum of a vector and other vector in the orthogonal complement of span? Welcome to MathSE! I noticed you've asked a few questions but have not accepted any answers. If you found any answers useful, you should start accepting them. Apr 4 comment Matlab coding help @DramaFreak: You should start accepting answers. Note that it goes with asking questions. Mar 28 comment Find the maximum dimensions that will strengthen rod Or is the strength proportional to $bh^2$ and not $(bh)^2$? Mar 28 comment Find the maximum dimensions that will strengthen rod So ... fit the biggest isoceles triangle in a circle of fixed diameter? Mar 25 comment Definition of sets You could say $p \in \mathbb{R}^2$ where $p = [x \quad y]^T$. So, $p$ is a point in $\mathbb{R}^2$ space. Mar 22 comment What does O(n+k) mean verbally @PooyaM: Don't you mean when $M = f(n)$? Mar 19 comment Two linearly independent vectors perpendicular to vector $u$ What does the equation $4x + 7y -9z = 0$ mean? It certainly means any point satisfying that equation is perpendicular to your vector. What does it mean graphically? Mar 18 comment Using the digits $7,7,7,7,1$ and the operators $+,-,*,/$ to make a formula which equals $100$ I'm assuming you can only use the digits once? And you can concatenate the digits to form number? Mar 7 comment What was the first bit of mathematics that made you realize that math is beautiful? (For children's book) +1 for $n(n+1)/2$. I "proved" this in the 5th grade using the same method :). Mar 7 comment Optimizing over norms of set of equations. Are you looking for a closed-form solution, code ... ? Feb 27 comment What does the value of a probability density function (PDF) at some x indicate? A good way of thinking about is $f(x) = \frac{dF}{dx}$ and so it's the rate of change of the cdf at $x$. Feb 27 comment What does the value of a probability density function (PDF) at some x indicate? This is a better answer than Alex's but doesn't explain the significance of the number $f(x)$. Does it have a meaning independent of a cdf? Andre's answer of it being approximately $hf(a)$ is great but he doesn't indicate if there's more to $f(x)$ by itself.