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0 votes
0 answers
37 views

What's the linearization of the product between a discrete variable and a continuous varibale?

I am trying to linearize the product $z=xy$, where $x$ is an integer variable and $y$ a continuous variable, both non-negative, for an optimization problem. I have tried the SCIP formulation: $v_{bn} \...
Ferran Cid's user avatar
2 votes
1 answer
223 views

Set a limit on value change of a binary variable

I am working on an Energy Management problem. The objective is to minimize the electricity bill for the customer. I have a time-series data with 15 min. intervals spanning the course of 1 year. The ...
Kushagr Goyal's user avatar
0 votes
2 answers
90 views

linearizing a constraint involving an absolute function

I would like to know what is the best way to linearize a constraint involving an absolute function. More precisely, imagine I have three binary variables and their relationships is as follows: |x-y| = ...
Sam's user avatar
  • 97
0 votes
1 answer
59 views

How to linearize this L0 norm of a vector?

I have an QP optimization problem. $\bf x$ is the binary optimizaion variable of size $12\times 1$. One of the constraints is non-linear/non-convex. The constraint is L0 constraint. The constraint I ...
KGM's user avatar
  • 2,377
0 votes
0 answers
116 views

why this little constraint changes my whole program?

I'm trying to linearize a CP in ILOG CPLEX. I have the following constraint that I want to linearize (I already simplified it with the big M) : ...
Marcocorico's user avatar
0 votes
0 answers
66 views

Why are these two constraint equations not equivalent?

I've made a CP Model of an hospital in ILOG CPLEX and I want to test the performance of the CPLEX version of it. In my CP model, I have the following constraint : ...
Marcocorico's user avatar
1 vote
0 answers
65 views

transform minimize weighted sum of absolute value into a linear optimization

For example, we have an optimization problem $$ \min \sum_{i=1}^{n} |w_{i} - a_{i}| b_{i} \quad \text{s.t.} \quad \sum_{i=1}^{n} c_i w_i = 0 $$ and $a_i, b_i, c_i$ are given. How to convert it into a ...
Pique's user avatar
  • 11
0 votes
1 answer
152 views

applying a piecewise linearized equation in pulp

The background is I'm building a toy rent vs. buy mortgage calculator. I am an experienced software engineer but my math skills are 20 years behind me and I admit to being very lost. I've been using ...
kashahkashah's user avatar
2 votes
1 answer
118 views

How to linearize the multiplication by a binary decision variable?

I am currently optimizing a hydrogen production chain. I am optimizing the production regime, and the size of the required wind, solar and the electrolyser. For every hour of the year, the production ...
KlaasR's user avatar
  • 23
2 votes
1 answer
148 views

How to show that minimizing the epsilon-insensitive loss is equivalent to a quadratic program with inequality constraints?

This question is about an optimization problem that arises in support vector regression (SVR). Suppose you have $N$ pairs $(\vec{x}_n, y_n)$ as data and would like to find a vector of weights $\vec w \...
ForceBru's user avatar
  • 123
3 votes
1 answer
109 views

using milp for a linear complementarity problem

I have to minimize $c^Tx$ subject to $Ax = b$, $x_iw_i = 0$ for all $i$, with $x$ non negative continuous and $w$ binary. What model should I use to solve this problem?
fischer justin's user avatar
1 vote
1 answer
58 views

$\min\{f(x_1),\dots,f(x_n)\}$ with other constraints

I have an optimization problem which goes: \begin{align*} \text{Minimize:} \\ & \sqrt{x} + \sqrt{y} \tag{NL-objective} \\ \text{Subject to:} \\ &3x + 2y \geq 2 &...
madhafakha's user avatar
3 votes
3 answers
286 views

Quantifying a measure of standard deviation in MILP

I am trying to set up a MILP for production scheduling. The specific details I'm not sure are important but in general a plant has M machines running N parts, each part requiring W workers. The model ...
Dano's user avatar
  • 55
0 votes
1 answer
292 views

Converting a piecewise function to a linear equation as a constraint

The value of one of the variable of my model (alpha_1) is given by a piecewise function. Each element of the piecewise depends on the value of some other binary decision variables (X1, x2, x3). I'd ...
Sam's user avatar
  • 97
1 vote
2 answers
224 views

Nonlinear fractional objective function

Could you please teach me when an optimization model with fractional terms in the objective function can be linearized or solved optimally? I only know that if the objective function has a single ...
Reza Farahani's user avatar

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