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2 votes
1 answer
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Finding zeros of a multi-variable nonlinear trigonometric function

I am trying to calculate analytic solution (or locus) of zeros of a very large multi-variable function which is consisted of thousands of nonlinear trigonometric terms. All the variables are real ...
p8me's user avatar
  • 123
3 votes
1 answer
862 views

Nonconvex optimization problem

I have a nonconvex optimization problem with a linear objective function, a set of linear constraints and a set of nonlinear, non-convex constraints. Is this problem NP-hard? If so, how can I prove ...
Star's user avatar
  • 221
3 votes
1 answer
602 views

Is the feasibility of a system of non-convex quadratic equations and inequations decidable?

I would like to know whether the following problem is decidable. Given the following system in $x \in [0,1]^n$ $$x^T Q_i x + r_i = 0 \mbox{ for } i = 1, ..., k$$ $$x^T Q_j x + r_j \neq 0 \mbox{ ...
Gavin's user avatar
  • 165
2 votes
0 answers
168 views

Recovering a partition from spectral properties of the graph Laplacian

Let $G$ be a weighted graph with vertices $V$. Let $W$ be its real-valued, non-negative, $|V|\times|V|$ adjacency/affinity matrix. Let $L = \mathrm{diag}(W\mathbf1)-W$ be the (unnormalized) graph ...
1 vote
1 answer
655 views

A non-convex quadratically constrained quadratic program

$$\begin{array}{ll} \text{minimize} & \beta^{T} A \beta\\ \text{subject to} & \beta^{T} C \beta=1\\ & \beta \geqslant 0\end{array}$$ where $A, C\in \mathbb{R}^{M\times M}$ and $\beta \in ...
Journey's user avatar
  • 13
4 votes
1 answer
396 views

Optimization problem - maximizing number of satisfied linear inequalities subject to a quadratic constraint

I am wondering what is known about optimization problems of the following type. Our control x is a unit vector in $\mathbb{R}^n$. We are given a finite number of linear inequalities $$Az≥b,$$ and we ...
user21277's user avatar
  • 185
0 votes
0 answers
104 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 |\lambda_2|(M)....
Umberto's user avatar
  • 105
4 votes
1 answer
128 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 cases where inexact ...
arbitUser1401's user avatar
2 votes
0 answers
242 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\times N}\mapsto \...
2 votes
3 answers
188 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 $F = a_1a_2 + a_2a_3 + \cdots + a_{n - > 1}a_n + a_na_1;$ with active ...
Francis's user avatar
  • 251
3 votes
1 answer
2k 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-side on a bench of a ...
Nathan West's user avatar
5 votes
1 answer
3k 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 information about a ...
Majid Yazdani's user avatar
0 votes
1 answer
654 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. I know in advance ...
George's user avatar
  • 3
4 votes
1 answer
2k 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 any one have ...
user32429's user avatar
0 votes
0 answers
189 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, variation of these ...
Star's user avatar
  • 221
7 votes
1 answer
422 views

Generalization of the equilateral triangle?

I consider points in the two-dimensional plane. An equilateral triangle is a set of three points in the plane which are equidistant. Suppose now I have $n$ points $x_1,...,x_n$. What is the ...
user16215's user avatar
  • 840
1 vote
1 answer
220 views

What kind of optimization problem is this?

I come across an optimization problem of the following form. $$\max {\frac{1+v}{1-u}} \qquad \text{s.t.} \qquad ux^2+vy^2-xy \ge 0, \quad \forall x,y\in\mathbb{R}$$ I do not know much of optimization. ...
Yuan's user avatar
  • 13
2 votes
0 answers
697 views

Find minimum-area ellipse enclosing a set of ellipses, all centered at the origin

Given a set of N > 2 (two-dimensional and coplanar) ellipses, all centered at the origin, how do I find the ellipse with the minimum area which encloses all of them? Background: Thanks to Will Jagy ...
Dave's user avatar
  • 21
6 votes
2 answers
2k views

Find minimum-area ellipse which encloses two ellipses

I need an efficient algorithm to find the ellipse with the smallest possible area which encloses two given ellipses. The given ellipses are constrained to have coincident centers at the origin but can ...
Dave's user avatar
  • 61
0 votes
0 answers
67 views

Minimizing inside a spherical uncertainty region

I am trying to figure out how to solve: $\min_U r_{p}$ where $r_{p}=\alpha^\intercal\omega$ and $U$ is a sphere centered at $\alpha$ with radius equal to $\chi|\alpha|$ . ( $\omega$ is a vector or ...
Geraldine Bailey's user avatar
0 votes
1 answer
319 views

Can one always Decide whether a Systems of Nonlinear Equations with Bilinear terms is Feasible?

I have come to a point in my PhD research were i need to prove that a particular decision procedure is decidable or not. And if i can solve the sub-problem described below, i shall have proved it. The ...
Gavin Rens's user avatar
2 votes
2 answers
293 views

Convex optimization problem to QPP

Briefly, have the following problem: \begin{equation} \sum_{i = 0}^n a_i \ (max [ F_i( \bar x ), 0 ] )^2 \rightarrow min, \\\\ s.t.\\\\ A \bar x \leq b \end{equation} where $ F( \bar x ) $ is a ...
Artem Pianykh's user avatar
6 votes
1 answer
1k 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 $\Theta, \forall k=1,\ldots,K$ are known, and are positive definite matrices. $\Omega$ also has to ...
Wei Liu's user avatar
  • 173
0 votes
1 answer
272 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 $A_2$ are $N\times N$ ...
dineshdileep's user avatar
  • 1,421
12 votes
2 answers
1k 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 combination of the ...
Seva's user avatar
  • 23k
5 votes
2 answers
429 views

Simultaneous maximization of two Generalized Rayleigh Ritz Ratios

Consider hermitian positive semi-definite matrices $A_1$ and $A_2$. Consider also positive definite matrices $B_1$ and $B_2$. I want to maximize the minimum of the two Generalized Rayleigh Ritz ratios ...
dineshdileep's user avatar
  • 1,421
0 votes
1 answer
165 views

Nonlinear matrix equation 2

Solve the following nonlinear equations for $v$ and $w$ $Avv^TAw+Bvv^TBw=\lambda_1v+\lambda_2w$ $Aww^TAv+Bww^TBv=\lambda_1w+\lambda_2v$ $v^Tw=w^Tv=0$ $v^Tv=w^Tw=1$ where $\lambda_1, \lambda_2, \...
Minh Tran's user avatar
2 votes
1 answer
1k views

Can one maximize the spectral norm of a matrix via semidefinite programming?

Consider the following optimization problem: Maximize $\|X\|_2$, subject to $X$ being Hermitian (or symmetric) and a bunch of semidefinite constraints on $X$. Here, $\|X\|_2$ is the spectral norm of ...
Robin Kothari's user avatar
1 vote
1 answer
2k views

linear objective function, non-linear constraints involving square-root of variables

i am trying to solve a general linear objective function with non-linear constraints. Can someone help me solve this. Here is an example of one problem i am trying to solve, minimize $b$ subject ...
Sainath Adapa's user avatar
3 votes
1 answer
793 views

Does Quadratic Programming get easier when it's described by a diagonal matrix?

Generally, Quadratic Programming solves the problem $$\text{Given }Q, c, A, b,\text{ choose }x \text{ to maximize } x^TQx + c^Tx \text{ subject to } Ax \le b$$ In this form, Quadratic Programming is ...
user21816's user avatar
  • 693
2 votes
2 answers
1k views

Minimizing product subject to linear constraints

I am looking for a solver that allows me to solve an optimization problem of the form $$\begin{array}{ll} \text{minimize} & x_1 x_2 \cdots x_n\\ \text{subject to} & \color{gray}{\text{(some ...
Guillermo's user avatar
1 vote
2 answers
242 views

what method can I employ to solve this optimization problem which involves \min?

The optimization problem is: maximize $$\min(\sum\limits_{i=1}^N \log\left(a_{1,i}+\frac{b_{1,i}}{c_{1,i}+d_{1,i}x_i}\right),\sum\limits_{i=1}^N \log\left(a_{2,i}+\frac{b_{2,i}}{c_{2,i}+d_{2,i}x_i}\...
zzzhhh's user avatar
  • 764
2 votes
1 answer
758 views

An algorithm for checking if a nonlinear function f is always positive

Is there an algorithm to check if a given (possibly nonlinear) function f is always positive? The idea that I currently have is to find the roots of the function (using newton-raphson algorithm or ...
Adel Ahmadyan's user avatar
1 vote
0 answers
784 views

Solving a system of complex non-linear equations

I have a set of five equations which can be described as follows: $m_{i}=\frac{k_{1}}{(x+a)^{i}} + \frac{k_{2}}{(b+d)^{i}}+ \frac{k_{3}}{c^{i}}$ for i=1 to 5 where $$\eqalign{ k_{1}&=\frac{a(x+...
aaaaaa's user avatar
  • 209
2 votes
2 answers
2k views

Solving a system of equations/inequalities that have trigonometric functions on the left-hand side

Is there any known (symbolic) method that solves a system of equations/inequalities that have trigonometric functions on the left-hand side of the system? Ex) Find $x,y,\theta \in \mathbb{R}$ that ...
SCL's user avatar
  • 23
1 vote
1 answer
370 views

A positive semidefinite programming problem

Dear all, I've got a SDP problem as follows: $\min_{{\bf H}\succeq0}\quad trace({\bf H}) - {\bf a}^{\top}{\bf H}{\bf b}$, where ${\bf a}$ and ${\bf b}$ are two constant vectors. May somebody tell ...
mintaka's user avatar
  • 145
1 vote
0 answers
266 views

Multiobjective semidefinite programming

Let $C$ be size $n \times n^{2}$. Let $B$ be size $2^{g(n)} \times n^{2}$ where $g(n) > n$. There is only one $\mathcal{1}$ per row of $C$ and remaining entries of $C$ are $\mathcal{0}$. $B$ is ...
user16007's user avatar
  • 800
1 vote
2 answers
847 views

maximizing multivariate polynomial

Consider $J = \sum_{i=0}^{N}y_{i-1}x_{i}y_{i+1}$ where $+$ and $-$ in the indices are mod $N+1$. Let $x_{i} = 1 - y_{i} \in \{0,1\}$. What are some of the tools useful and relaxation techniques ...
Turbo's user avatar
  • 13.9k
-1 votes
2 answers
487 views

Any efficient software/package/toolbox for nonlinear programming for MATLAB

I want to solve a nonlinear programming problem with the objective function being coded as a recursive function in Matlab. I have tried “fmincon”, but it could not get the solution due to large number ...
Bing's user avatar
  • 1
9 votes
5 answers
646 views

Software for rigorous optimization of real polynomials

I am looking for software that can find a global minimum of a polynomial function over a polyhedral domain (given by, say, some linear inequalities) in $\mathbb R^n$. The number of variables, $n$, is ...
Boris Bukh's user avatar
  • 7,836

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