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visits member for 3 years, 3 months
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Aug
12
comment What is the oldest open problem in geometry?
I would like to see an animation for a periodic orbit in an obtuse triangle.
Jul
24
revised Probability with Uniform Distribution with Multiple Variables
texified the body
Jul
24
suggested suggested edit on Probability with Uniform Distribution with Multiple Variables
Jul
11
comment Limit of the integral: $\int_0^{\pi/2}\beta^\alpha\exp\left(-\beta\cos(\theta)\right)d\theta$
Shouldn't it be $\lim_{\beta\to+\infty}J_0(\beta)=0$? Illustration.
Jul
4
comment 'Obvious' theorems that are actually false
You may be interested in these books: Counterexamples in Analysis, Counterexamples in Topology, and Counterexamples in Probability.
Jul
2
comment How to prove that: $\tan(3\pi/11) + 4\sin(2\pi/11) = \sqrt{11}$
How did you reach the $\sum_i \omega^{2i}=0$?
Jul
2
awarded  Curious
Jun
19
revised Find an invertible matrix $P$ and a diagonal matrix $D$ such that $D=P^{−1}AP$?
Texify the title
Jun
19
suggested suggested edit on Find an invertible matrix $P$ and a diagonal matrix $D$ such that $D=P^{−1}AP$?
Jun
19
comment How to evaluate the following integral? $\int \ln(e^x + c)~\mathrm dx$
When faced with $\int f(e^x)\,\mathrm{d}x$, try transform it into $\int u^{-1}f(u)\,\mathrm{d}u$.
Jun
19
comment Clarification on optimization problem
I think for any $\alpha_k$, the objective function is linear. Given that the constraint is also linear, the optimum lies in some corner point. Since $\alpha_5=1$ violates the constraint, so $\alpha_5=0$.
May
17
awarded  Yearling
Apr
20
comment Givens rotation and retraction mapping
Thanks. I am fine with the QR/polar decomposition and exponential mapping, but I am not clear about the part of Givens rotation in the text. Also, any references for the "closest" property of polar decomposition?
Apr
19
asked Givens rotation and retraction mapping
Apr
9
awarded  Notable Question
Mar
25
accepted Generic points as coefficients of polynomial kernels?
Mar
24
revised Generic points as coefficients of polynomial kernels?
edited title
Mar
24
asked Generic points as coefficients of polynomial kernels?
Feb
18
comment Homework problem on continuity
I think differentiability implies continuity.
Jan
23
comment $QQ$-plot - Why do we choose the empirical distribution $F_n(x) = \frac {\#\{y \in S \mid y \le x\}} n$, $S$ is sample, for comparison with normal?
Just to mention that there is another SE site for statistics: stats.stackexchange.com