Questions tagged [mathematical-optimization]

Mathematical optimization deals with maximizing or minimizing an objective function by choosing values from within an allowed feasible set of possible values. Mathematical optimization is often also referred to as mathematical programming or simply as optimization.

Mathematical optimization deals with maximizing or minimizing a real function by choosing values from within an allowed feasible set of possible values. Mathematical optimization is often also referred to as mathematical programming or simply as optimization.

Thus, the study of Mathematical optimization includes formulating the problem (as a set of mathematical equations), and developing several solution techniques. These techniques exploit the underlying structure of the problem. Different optimization algorithms are suited for different types of problems and vary in solution times and computational complexity.

The goal (to be maximized or minimized) is called the "Objective Function." The set of equations that limit the solution space are the "constraints" and the possible solution space is the "feasible region." In some problems, the aim is to just find any acceptable solution, and these are called "constraint satisfaction problems" in which case there is no real objective function to be minimized or maximized.

Broadly, Mathematical Optimization falls under the area of "Applied Mathematics."

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How do I mathematically represent affine transform of an image?

I have 2 grayscale images A and B. I am performing an affine transform (rotation and translation) on B. I am then calculating the standard deviation of (A-B*), where B* is: B* = affine_transform(B) I want to run gradient descent to find optimal…
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Optimizing number of workers scraping a website

I'm interested in scraping a particular website periodically that has ~100 million items on it. The scraper can download and process items very quickly, on the order of 50ms, but even at that speed it will take days to complete. The obvious…
Allyl Isocyanate
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Should I linearize or try to solve the MINLP in python with gurobi or try a completely different approach?

I'm fairly new to this, so I'm just going to shoot and hope I'm as precise as possible and you'll think it warrants an answer. I'm trying to optimize (minimize) a cost/quantity model, where both are continuous variables. Global cost should be…
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Distribute associative array elements into groups with a maximum sum per group

I need to split my associative array into bunches of not greater than 50 in each bunch. Multiple elements may be pushed into a given group to ensure that a group reaches 50 before starting a new group. Sample input: $array = [ '5' => 142, …
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A variant of the Knapsack algorithm

I have a list of items, a, b, c,..., each of which has a weight and a value. The 'ordinary' Knapsack algorithm will find the selection of items that maximises the value of the selected items, whilst ensuring that the weight is below a given…
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Constraints for Minimizing and their Bounds

I have a little confusion in the optimization model I trying to solve. Its a small model to minimize the cost of two units. I have just started with the optimization and I am not sure if I am interpreting the problem very well into AMPL. Especially…
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Error in minimization using scipy

I am trying to minimize a function using spicy but the estimate of sigma is way off. Any help would be greatly appreciated. Here's my code so far:- import numpy as np from scipy.optimize import minimize import matplotlib.pyplot as plt import…
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Spark (Scala) - how to optimize objective function parameters

I have function f going from R2 to R which takes 2 parameters (a and b) and returns a scalar. I would like to use an optimizer to estimate the values of a and b for which the value returned by f is maximized (or minimized, I can work with -f). I…
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ojAlgo - Optimization issue with contiguous block logic?

I am using ojAlgo to work through a classroom scheduling problem I'm doing as an exercise. The source code can be found here on GitHub in the kotlin_solution folder: https://github.com/thomasnield/optimized-scheduling-demo Everything was going fine…
tmn
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Product of Two Variable in Integer Programming Objective

I'm trying to create an optimization problem in the following form using lpSolveAPI. max 10(x1 + x2) * S1 + 20(x1 + x2) * S2 sub.to. S1 + S2 <= 1 # These are binary variables. 2 * x1 + 3 * x2 <= 30 1 * x1 + 2 * x2 <= 10 x1 & x2 are integers. My…
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Use mod function in a constraint using Python Pulp

I am writing a LpProblem and I need to create a constraint where the sum of some variables is multiples of 100... 100, 200, 300... I am trying the next expressions using mod(), round() and int() but none works because they don't support…
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Applying Bender's decomposition using CPLEX example

I want to implement bender's decomposition method using CPLEX example in my model. The function works but the results are not correct. I should mention that the objective value of my master problem at the beginning is zero, then the variables values…
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Self reference in @expression statement in Julia

I am still quite new in Julia but I was wondering if there is a way to make a self reference in an @expression statement in JuMP. For instance I would like to be able to make this statement: n = 3 @expression(model_opt, D[i=1:9], i>n ? D[i-n] :…
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How to add a constraint to my optimization?

I am working on formulating an optimization problem where I have a 2-D matrix A. A= [0 f1 0 f2] [f3 f3 0 0] ......... And I have another 2-D matrix B that I should fill. B has the same size of A. I need b_ij…
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What is the time and space complexity of SLSQP minimize algorithm in Scipy?

I mean the following method: scipy.optimize.minimize(method=’SLSQP’) I heard in this issue that the "The memory required by COBYLA and SLSQP is quadratic in the number of variables. These algorithms are not suitable for solving such large…