0
votes
0answers
38 views
Big eigenvalues of a special stochastic matrix
Given a matrix $M$ of size $n\times n,$ we write its different eigenvalues by $x_1,x_2,\ldots,x_m$ with $m\leq n$ such that $|x_1|>|x_2|>|x_3|>\cdots|x_m|,$ and call $x_2\doteq |\l …
1
vote
1answer
29 views
Conjugate gradient algorithm where first search direction is not equal to residual
In usual formulation of conjugate gradient algorithm initial search direction is taken to be the residual (so residual and search direction spans Krylov subspace). However, in case …
2
votes
0answers
75 views
Quadratic optimization with parameter in constraint
Disclaimer: I posted the same question on math.stackexchange. However, the FAQ suggests to post research-level questions in this forum.
Question: Given a function $q: \mathbb R^{N …
3
votes
3answers
125 views
Constraint optimization problem for any dimensionality $n>1$.
I am going to post a particular example for the sake of clarity.
One needs to maximize a real function
$F = a_1a_2 + a_2a_3 + \cdots + a_{n -
1}a_n + a_na_1;$
wit …
3
votes
1answer
349 views
The average number of people that can sit on a bench of a given length.
Let me explain what I mean:
The width of the average person varies, perhaps with a normal distribution.
Given a specific variance, how many people (on average) can sit side-by-si …
2
votes
1answer
66 views
Maximizing supermodular functions
I have a real supermodular objective function which I want to maximize with constraint. The constraint is on the size, like |A|=k .
I am wondering if anyone can give me more inf …
0
votes
0answers
105 views
minimum of some functions
Denote $U=\{(x_1,x_2,...,x_n):x_j\in(0,1) (1\le j\le n),\sum_{j=1}^nx_j=1\}$.
Let $f_i=f_i(x_1,x_2,...,x_n)$ ($1\leq i\leq n-1$) be $n-1$ real functions which satisfy:
$\prod_{i …
0
votes
1answer
42 views
minimization of a function when the feasible set is an unbounded cone
I have the following semi-infinite programming problem: I need to minimize a strictly convex real-valued function $f:\mathbb R^n\to\mathbb R$ subject to infinite linear constraints …
0
votes
0answers
57 views
Optimal instance of quadratically constrained program
Consider the following optimization problem. Let $n, m \in \mathbb N$ and $0 < p_1 \leq \ldots \leq p_n ~ (p_i \in \mathbb R)$ be constant. The feasible region is described by a …
1
vote
1answer
82 views
lipschitz constant of a multivariate function
I have a function $f:\mathbb{R}^{50} \rightarrow \mathbb{R}$ and I need to compute the Lipschitz constant of $f$ to solve an optimization problem using a specific algorithm. Does a …
1
vote
1answer
109 views
What kind is this optimization problem
I come across a problem like
$\max {\frac{1+v}{1-u}}$
$s.t.~$ $ux^2+vy^2-xy\ge0$ $\forall x,y\in\mathbb{R}$
I do not know much of optimization.
What I have done is that $ux^2+vy …
0
votes
0answers
34 views
functional maximization
Define a functional space of functions of the form $F(t)=p_1 exp^{-\mu_1(\delta-t)}+p'_1 (1-exp^{-\mu_1(\delta-t)}))$. $p_1,p'_1,\delta,\mu$ are parameters in [0,1] and trivially, …
11
votes
2answers
405 views
Quadratic Farkas' Lemma?
The Farkas Lemma says that if a system of linear inequalities implies
yet another linear inequality, then this last inequality can be obtained by
taking a positive linear combinati …
5
votes
1answer
224 views
Solve equation with matrix variable
I want to solve a matrix $\Omega$ from a equation $\sum_k (\Omega + \Theta_k)^{-1} = Q$. The $Q$ and $\Theta, \forall k=1...K$ are known, and are positive definite matrices. $\Omeg …
0
votes
1answer
138 views
A certain type of quadratic problem.
I am interested in solving the following equality constrained quadratic (?) problem.
\begin{align}
\min_{u^{H}u=1}~(u^{H}A_1u) \\
s.t.~ u^{H}A_2u=0
\end{align}
$A_1$ and $A_2$ …

