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Analytical solution for equality-constrained QCLP

I'm looking for a way to derive a closed form expression for $\omega$, which is the solution of the following maximization problem: $$\max_{w} \omega^{T}\mu$$ $$\textrm{st.}\hspace{0.5cm} \omega^{T}\...
T123's user avatar
  • 123
1 vote
2 answers
260 views

Linear program plus sphere constraint

I have the following optimization problem: \begin{align} \min_{x} \quad & x^\top \hat{x} \\ \text{s.t.} \quad & x^\top a_i \leq 0, \quad \forall i \in \{ 1,\ldots,N \} \\ & \|x\|_2 = 1, \...
durdi's user avatar
  • 783
0 votes
0 answers
90 views

Dual formulation of a QCLP

I'm working on a quadratic constrained linear program (QCLP) which I'm trying to obtain its dual formulation. I would like this formulation to be linear, or at least convex. Here are my results so far....
aparedes's user avatar
1 vote
0 answers
109 views

Solving a QCLP with both equality and inequality quadratic constraints

I have the following quadratically-constrained linear program (QCLP) $$ \begin{array}{ll} \underset {x} {\text{minimize}} & -c^T x \\ \text{subject to} & x^T Q x \leq a^2 \\ & x^T L x = 1 \...
Renganathan Subramanian's user avatar
2 votes
1 answer
76 views

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 \...
Jiachun Jin's user avatar
1 vote
3 answers
114 views

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 ...
Ryan's user avatar
  • 697
2 votes
1 answer
122 views

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) :=...
ji zhi's user avatar
  • 21
0 votes
1 answer
342 views

Explicit solution of an QCLP

Give an explicit solution of the following QCLP $$\begin{split} & c^\top x \to \min\limits_{x \in \mathbb{R}^n }\\ \text{s.t. } & x^\top A x \leq 1\end{split}$$ where $A \in \mathbb{S}^n_{++}$ ...
Alex Scain's user avatar
1 vote
1 answer
91 views

Sketch the graph of $ f (x_1, \: x_2) = x_2 $ over $ x_1 ^ 2 + x_2 ^ 2 \leq 2 $ and find the maximum value of $ f $.

Sketch the graph of $ f (x_1, \: x_2) = x_2 $ over $ x_1 ^ 2 + x_2 ^ 2 \leq 2 $ and find the maximum value of $ f $. The graph would be what's inside the cylinder, I think. My affirmation is that the ...
Gabriela's user avatar
  • 880
0 votes
1 answer
727 views

Maximize $f(x,y) = x+y$ subject to $x^2+xy+y^2+y=1$

I'm stuck trying to find the maximum value and at which point it occurs of the function $$f(x,y) = x + y,$$ subject to the constraint $x^2 +xy +y^2 + y = 1$. my working so far is $f_x = \lambda g_x \...
Glacial's user avatar
1 vote
2 answers
141 views

How can I solve this maximization problem with inequality constraint on the Frobenius norm?

$$ \max_{C\in \mathbb{S}^n} x^TCx\\ s.t. \|C\|_{tr}^2\leq b $$ where $\|C\|_{tr}^2=tr(C^TC)=tr(CC)$, $C$ is a symmetric matrix.
Liangyu Min's user avatar
1 vote
1 answer
390 views

Solve with KKT min $x_1-4x_2+x_3$

Given min $x_1-4x_2+x_3$ s.t $x_1+2x_2+2x_3=-2$ $||x||^2\leq1$ (i)Given a KKT point of the problem above,must it be an optimal solution? (ii) Find the optimal solution of the problem using KKT ...
convxy's user avatar
  • 1,898
0 votes
1 answer
282 views

Linear objective with quadratic equality constraint

I've been given a problem: min $f(x) = c^Tx$ s.t. $\sum_{i}x_i = 0$ $\sum_{i}x^2_i$ = 1 I've created the Lagrangian function $L(x,\lambda) = c^Tx - \lambda_1\sum_{i}x_i - \lambda_2\left(\left(\sum_{i}...
mathcomp guy's user avatar
0 votes
0 answers
330 views

Solve Mean-Variance Problem by Expected Return Maximization

One period market with n securities with return R~ $N(\mu,\Sigma)$. An expected return on each security is $\mu_1,\dots,\mu_n$ Investor has 1 unit of wealth and invests into n assets, with weights $...
Harry Lew's user avatar
  • 128
1 vote
1 answer
221 views

Maximize $a^T x$ with constraint on $2$-norm of $x$

In a textbook i'm reading, a maximization statement is given to maximize $a^Tx$ where the 2-norm of $x$ is smaller or equal than $c$, where $a$ and $x$ are vectors and $c$ is a scalar. The answer is ...
user3053216's user avatar
1 vote
2 answers
2k views

Linear program with quadratic (L2 norm) constraint

I would like to solve an optimization problem of the type $$ \min_x x^T c, \quad s.t. \|x\|_2 \leq k \; \land \; a \leq x_i \leq b \; \forall i$$ efficiently (note the quadratic norm constraint), ...
Eike P.'s user avatar
  • 148
0 votes
2 answers
1k views

Lagrange Multiplier Find Maximum and Minimum

Use Lagrange multiplier to find maximum and minimum of $f(x,y) = 3x-4y$ subject to $x^2+3y^2=129$. So I start by getting the partial with respect to both f(x, y) and $x^2+3y^2=129$ Ultimately, I get ...
OGK's user avatar
  • 173
2 votes
1 answer
189 views

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(...
kkcocoqq's user avatar
  • 306
3 votes
1 answer
728 views

Constrained convex optimization [duplicate]

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 ?
rgk's user avatar
  • 29
0 votes
3 answers
98 views

Minimize with Lagrange multiplier

$$\begin{array}{ll} \text{minimize} & f(x,y,z) := x+2y+z\\ \text{subject to} & g(x,y,z) := x^2+y^2+z^2-1=0\end{array}$$ I get the following $\nabla f=(1,2,1)$ and $\nabla g=(2x,2y,2z)$. Now, ...
user avatar
1 vote
1 answer
167 views

Minimize $x + z$ subject to $x^2 + y^2 = 1$ and $y^2+z^2 = 4$

I'm trying to solve this problem by KKT's condition: $$\begin{align*} \text{min} & \quad x + z \\ \text{s.t} & \quad x^2 + y^2 = 1 \\ & \quad y^2+z^2 = 4 \end{align*}$$ One ...
Akira's user avatar
  • 17.9k
1 vote
2 answers
259 views

Minimise $2x+y$ subject to $x^2+y^2=1$ using KKT

I'm doing this exercise in preparing for the final exam in optimization: $$\begin{align*} \text{min} &\quad 2x+y \\ \text{s.t} & \quad x^2+y^2=1 \end{align*}$$ Could you please verify if I ...
Akira's user avatar
  • 17.9k
2 votes
2 answers
441 views

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 $\...
fire-bee's user avatar
  • 332
1 vote
1 answer
143 views

Change of variables in QCLP

Is there any change of variables that makes the following optimization problem easier to solve? \begin{align} \max_{x\in\mathbb{R}^n,t\in\mathbb{R}}\quad & c^\top x,\\ \mbox{s.t.}\quad\quad & ...
Farhad's user avatar
  • 25
0 votes
0 answers
208 views

Constrained optimization problem exam question

Consider the following constrained optimization problem: $$\min_{x} f = x_1 \\ \text{such that} \quad g_1=x_1^2+x_2^2-9 \leq0 \\ \qquad \qquad \ \ \quad \ g_2=-x_1^2-x_2^2+4 \leq0 \\ \qquad \ \ \ \ \ ...
user463102's user avatar
2 votes
0 answers
277 views

"Convert" quadratic constraint to quadratic objective

I have a large sparse quadratic optimization problem with a single quadratic constraint: $$\begin{array}{ll} \text{maximize} & c'x\\ \text{subject to} & l \leq Ax \leq u\\ & x'Qx + b'x \...
user10203644's user avatar
1 vote
1 answer
94 views

Finding maximum of $y-z$ given quadratic constraint

Problem According to my friend, this is a problem that seems to be solvable by observation. Try to find the maximum of $(y-z)$ given following two constraints $$ \begin{aligned} x+y+z=3\\ x^2+y^2+z^...
Mr.Robot's user avatar
  • 666
1 vote
1 answer
83 views

Find a minimum and a maximum of expression $E(x,y,z)=x-2y+z$

Find minimum and maximum of $E(x,y,z)=x-2y+z$ where $2x^2+y^2+z^2=3$. For finding the maximum of the expression I first thought using the inequality of Cauchy-Buniakowski-Schwarz: $$\boxed{(ax+by+cz)^...
C. Cristi's user avatar
  • 3,313
3 votes
2 answers
85 views

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. ...
Mario Zelic's user avatar
0 votes
1 answer
66 views

Optimization of linear objective with quadratic integer constraint

Is there any way to solve an linear optimization problem with quadratic integer constraint? E.g. $\max a^Tx$, $x=\langle x_1,x_2,\cdots,x_n \rangle$ s.t. $x_ix_j<b_{ij}$, $\forall x_i,x_j \in x$ ...
MonsterWhat's user avatar
2 votes
1 answer
279 views

Optimality condition for convex QCLP

I am trying to get the optimality condition for the following problem $$\begin{array}{ll} \text{minimize} & c^T y\\ \text{subject to} & Ay = 0\\ & y^T B y \le 1\end{array}$$ where $B$ is ...
david's user avatar
  • 83
2 votes
1 answer
713 views

Optimization of linear objective with non-convex quadratic constraint

Is there any technique to deal with a problem where we have a linear objective function and one or many quadratic non-convex function(s) like the problem below? $$\begin{array}{ll} \text{minimize} &...
Sourav Mondal's user avatar
1 vote
1 answer
306 views

Boolean quadratically constrained linear program (QCLP)

1) I have the following problem that I would like to first solve optimally but I have not been able to express it in a way that can be accepted by Matlab optimization functions. $$\begin{array}{ll} ...
Duns's user avatar
  • 778
1 vote
1 answer
2k views

Solving linear program with 1 quadratic constraint complexity

Consider the following linear program, $$\min y \\ xc_1 \leq c_2 + yz,\\ x = x_1 + \dots + x_n,\\ z \leq x_1 + x_2, \\ z \leq x_2 + x_3, \\ \vdots\\ z \leq x_{n-1} + x_n, \\ x,x_1, \dots, x_n,y,z \...
karmanaut's user avatar
  • 741
6 votes
4 answers
116 views

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 ...
Angelo Mark's user avatar
  • 6,058
2 votes
3 answers
857 views

Determining the minimum of a linear function subject to a quadratic inequality constraint

What is the minimum value of $x+4z$, a function defined on $\mathbb{R^3}$, subject to the constraint $x^2 + y^2 +z^2 \leq 2$? I know how to solve this if the constraint is an equality, but what shall ...
user avatar
0 votes
1 answer
349 views

Maximize $\mbox{tr} (AX)$ subject to $\mbox{tr} (BX'CX) = 1$

Suppose $A,B,C$ are given square matrices and $X$ is a matrix variable. Is there a nice way to express the following? $$\begin{array}{ll} \text{maximize} & \mbox{tr} (AX)\\ \text{subject to} &...
Yaroslav Bulatov's user avatar
0 votes
0 answers
589 views

Python solver for a linear objective function with quadratic constraints

I need to optimize a problem of the following form within Python $ minimize$ $\qquad abs(\Delta w) \;\epsilon^T$ $s.t.$ $\qquad(w+\Delta w)C(w+\Delta w)^T \; \le 9500 (some\; finite\; number) \\\\[...
Rehan's user avatar
  • 1
1 vote
2 answers
608 views

How to solve this convex optimization problem (with absolute and linear objective function)?

I have the following problem: \begin{align*} \sup_y&\quad \big | \langle u,y \rangle\big |\\ \mbox{s.t.}&\quad \frac{1}{2}\langle y,y \rangle\ + \langle b,y \rangle\ \geq \gamma. \end{align*...
sleeve chen's user avatar
  • 8,485
3 votes
2 answers
2k views

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 (...
Preetam Pal's user avatar
3 votes
1 answer
311 views

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_{...
user402078's user avatar
1 vote
1 answer
121 views

How to maximize $\langle X, Y \rangle$ over $X$ under constraint s.t $\mbox{Tr} (X^TAX)=1$?

Maximize $\langle X, Y \rangle$ over $X$ subject to the constraint $\mbox{Tr} (X^TAX) = 1$. Here $A$ is positive semi-definite and also all matrices have real entries and $Y$ is a known matrix given ...
user251385's user avatar
0 votes
4 answers
196 views

Maximize $\langle \mathrm A , \mathrm X \rangle$ subject to $\| \mathrm X \|_F = 1$

Given $\mathrm A \in \mathbb R^{m \times n}$, $$\begin{array}{ll} \text{maximize} & \langle \mathrm A , \mathrm X \rangle\\ \text{subject to} & \| \mathrm X \|_F = 1\end{array}$$ I can think ...
Rodrigo de Azevedo's user avatar
2 votes
2 answers
3k views

Minimize linear objective subject to unit norm constraint

I have a linear function with unit norm constraint that I need to minimize. $$\begin{array}{ll} \underset{w}{\text{minimize}} & w^\top x\\ \text{subject to} & \|w\| = 1 \end{array}$$ Is ...
TrueWheel's user avatar
  • 143
7 votes
1 answer
4k views

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 \...
Thesinus's user avatar
  • 1,242
3 votes
3 answers
2k views

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(...
user1234's user avatar
1 vote
2 answers
614 views

Linear programming with non-convex quadratic constraint

Could anyone let me know if the following linear programming problem can be solved in polynomial time or should be NP-hard? $\min c^Tx$ s.t. $x^TQx\geq C^2, x\in [0,1]^n,c\in \mathbb{R}_+^n,Q\in\...
Peter J.'s user avatar
11 votes
2 answers
4k views

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 $n \times n$ ...
user123346's user avatar
3 votes
1 answer
3k views

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.
Priyanka's user avatar