Questions tagged [qclp]

A quadratically constrained linear program (QCLP) is an optimization problem in which the objective function is linear and the constraints are quadratic.

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Linear programming with one quadratic equality constraint

I have a problem that can be formulated as a linear program with one quadratic equality constraint: where variable $x$ is an $n$-dimensional vector and $H$ is a positive semidefinite $n \times n$ matrix. I know this optimization problem can always…
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If $a,b$ are positive integers and $x^2+y^2\leq 1$ then find the maximum of $ax+by$ without differentiation.

If $x^2+y^2\leq 1$ then maximum of $ax+by$ Here what I have done so far. Let $ax+by=k$ . Thus $by=k-ax$. So we can have that $$b^2x^2+(k-ax)^2 \leq b^2$$ $$b^2x^2+k^2-2akx +a^2x^2-b^2\leq 0 $$ By re-writing as a quadratic of $x$…
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Maximizing a linear function over an ellipsoid

Let $A \in \mathbb{R}^{n\times n}$ be a positive definite matrix, $x \in \mathbb{R}^n$ and $c \in \mathbb{R} \setminus \{0\}$. Determine the maximum $$ \max_{y \in \mathbb{R}^n} \left\{ c^T y : y \in \mathcal{E} (A,x) \right\} $$ where $\mathcal{E}…
Thesinus
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Constrained convex optimization

Solve Maximize $f(x)=c^Tx$ subject to $x^TQx \leq 1$ where $Q$ is a positive definite matrix. what is the solution if the objective function is to be minimized ?
3
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Lagrange multiplier when decisions variables are not in the same set

Find the maximum of $2x+y$ over the constraint set $$S = \left\{ (x,y) \in \mathbb R^2 : 2x^2 + y^2 \leq 1, \; x \leq 0 \right\}$$ I want to use Lagrange multipliers to find the optimal solution. However, Lagrange requires $\vec x \in A$. In our…
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Linear objective function with quadratic constraints

The context is ordinary multivariate regression with $k$ (>1) regressors, i.e. $Y = X\beta + \epsilon$, where $Y \in \mathbb{R}^{n \times 1}$ vector of predicted variable, $X \in \mathbb{R}^{n \times (k+1)}$ matrix of regressor variables(including…
3
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Indefinite quadratic constraint

I'm trying to solve an optimization problem with a linear objective function and mostly linear constraints. However, I do have several constraints of the form $$\sum_{i=1}^m x_i\phi_i - \left(\sum_{i=1}^m x_i\right) \left(\sum_{j=m+1}^n x_j\right)…
3
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3 answers

Linear programming with quadratic constraints

I have a given set of variables: $x_1,y_1,x_2,y_2,x_3,y_3$ The objective function is to minimize the sum of these with quadratic equality constraints: $y_1(x_1+x_2+x_3)$=0 $y_2(x_2+x_3)$=0 $y_3(x_3)$=0 There are other inequality constraints which…
user1234
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How to solve a quadratically constrained linear program (QCLP)?

Can anybody suggest some techniques to solve a quadratically constrained linear program (QCLP)? Any references on standard techniques would be helpful.
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Find infimum and supremum of the function $f$ defined by the formula $f(x, y, z) = 2x+ 2y-3z$ on the set $A$

Let $A = \{(x, y, z) \in \mathbb R^3 : x^2 + y^2 + z^2 = 2, xy + yz +zx +1 = 0\}$. Find infimum and supremum of the function $f$defined by the formula $f(x, y, z) = 2x+ 2y-3z$ on the set $A$. I want to use Lagrange multipliers so I got the…
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1 answer

Gradient of Lagrangian can not be set to 0

I am trying to solve the following constrained optimization problem: $$ \begin{array}{rl} \underset{V \in \Bbb R^{D \times d}}{\operatorname{minimize}} & \operatorname{trace} \left( W V^\top \right) \\ \text{such that} & \frac12 x^\top VFV^\top x =…
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How to deal with the constraint $a \leq \|x\|_2 \leq b$ in an optimization problem?

How to solve the following optimization problem? $$\begin{array}{c l} \underset {x} {\text{minimize}} & c^{\top} x\\ \text{subject to}~& a \leq \|x\|_2 \leq b \end{array} $$ Can we convert it into a convex optimization problem?
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Maximizing linear objective subject to quadratic equality constraint

I've been trying to get through some practice questions on the Karush-Kuhn-Tucker (KKT) theorem but I can't seem to answer the following. Given $f, g : \mathbb{R}^2 \to \mathbb{R}$ defined by $f(x) := x_1 + x_2$ and $g(x) :=…
ji zhi
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Optimizing Trace$(Q^TZ)$ subject to $Q^TQ=I$

Let $Z \in \mathbb{R}^{m \times n}$ be a tall matrix ($m > n$). Solve the following optimization problem in $Q \in \mathbb{R}^{m \times n}$ $$\begin{array}{ll} \text{maximize} & \mbox{Tr} \left(Q^T Z \right)\\ \text{subject to} & Q^T Q = I_{n…
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Maximisation of a piecewise affine function over an ellipsoid

Given vectors $\mathrm a, \bar{\mathrm x} \in \mathbb R^n$ and matrix $\mathrm P \in \mathbb S^n_{++}$, how to deal with the absolute value in the objective function of this optimization problem in $\mathrm x \in \mathbb R^n$? $$\begin{array}{ll} …
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