All Questions
563 questions with no upvoted or accepted answers
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A linear program related question
Dear all, recently, I encountered the following problem. It is closely related to the order of growth for UMD constants of all $n$-dimensional Banach lattice.
Let $\alpha^k \in (\alpha_1^k, \alpha_2^...
- 769
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79
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Computing maximum point for minimal function of a family of linear functions
Let $x \in S^n $ where $S^n = ${$ [x_1,x_2,...,x_{n+1}]\in \mathbb{R}^{n+1} \mid x \ge 0 , \sum x_i = 1 $} and let $f_i : I^n \to \mathbb{R}$ be a finite $m$-sized family of LINEAR functions such that:...
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783
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LP relaxation for ILP\IP (integer linear programming)
I am familiar with LP relaxation for ILP (or IP). Assume we concern with integer minimization problem, which we formalize using ILP; we then relax the ILP into LP and we say that the LP provides a ...
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Finding peaks and determining noise
Hello ,
Im having one matrix which is product of two FFT transforms of one fits image ( astronomical image ). In that matrix you could find 3 peaks. One largest in center, and two around central ...
- 101
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sparsest cut always has solution
Hi!
How to prove that sparsest cut always has an optimal solution which is the cut for some vertex-subset.
Looks like it's should be a kind of fundamental theorem for sparsest cut. But I didn't ...
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125
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functional iteration
This is a past prelim question,
Let $F(x)=2x+qx^2$ with $\frac{1}{2}\leq q \leq 1$ and $x_{n+1}=F(x_{n})$.
For which interval does this iteration converge ?
I tried these but did not work;
Fixed ...
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727
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Decomposing max-convolution of sum of functions ?
Hello.
$R, F_1, F_2, F_3$ are random (not-convex, not-concave) 2D matrices of size 100x100.
$R$ is a linear combination of $F_1, F_2, F_3$.
Explicitly, $R = w_1 F_1 + w_2 F_2 + w_3 F_3$
where $w_1,...
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519
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Even least squares approximation
Let's consider $\theta_n$ a class of approximations with the following properties:
- all functions $\phi \in \theta_n$ are defined on a symmetric interval [-a, a];
- if $\phi(t)\in\theta_n$, then $\...
- 1
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285
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Linear combination of finite difference weights and generalized increments
According to a paper I'm reading ("Linear estimation of non stationary spatial phenomena", by P. Delfiner) the weights $\lambda_i$ and $\lambda_{i - 1}$ of a first order finite difference $Z(x_i) - Z(...
- 661
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319
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Estimating a multinomial sum
I have the following sum
\begin{equation}
\sum_{r_1=q+1}^{\tau}\dots\sum_{r_\lambda=q+1}^{\tau}{\tau\choose r_1,\dots,r_\lambda,\tau-r_1-\dots -r_\lambda} (\Lambda-\lambda)^{\tau-r_1-\dots-r_\lambda}
\...
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445
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Value of coefficient in estimation of computational complexity of polynomial division algorithm
Do you know value of coefficient $C$ at $C*n*log(n)$ in $O(n*log(n))$ estimation of complexity of polynomial division algorithm?
It would be great if you give me links to paper with information about ...
- 424
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1
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181
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A simple procedure to simulate multifractional Brownian motion paths
In a paper by Peltier and Vehel the multifractional Brownian motion (mBm) was defined for the first time, and they also give a procedure to simulate mBm sample paths. Briefly, mBm generalizes the ...
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Best approximation of the modulus function
While there is extensive study regarding the best approximation of function with polynomial functions in the real domain, the study of approximation of complex variables becomes much sparse. See this ...
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