How to minimise this function and get initial conditions

Click For Summary
SUMMARY

The discussion focuses on minimizing the linear function ra = min(00237 − 0000175v + 8.693f − 000159y) under specific constraints for variables v, f, and y. It is established that the minimum value for a linear function defined on a convex set, such as a rectangular solid, occurs at a vertex. The provided values of v = 144.2, f = 0.025, and y = 9.5 do not correspond to any vertex within the defined constraints, indicating that these values do not yield a minimum. The coefficients in the function require clarification regarding their decimal placement for accurate interpretation.

PREREQUISITES
  • Understanding of linear programming and optimization techniques
  • Familiarity with convex sets and their properties
  • Knowledge of function minimization in mathematical contexts
  • Ability to interpret and manipulate mathematical expressions and coefficients
NEXT STEPS
  • Study linear programming methods using tools like MATLAB or Python's SciPy library
  • Explore the properties of convex sets and their implications in optimization
  • Learn about vertex solutions in linear optimization problems
  • Investigate the significance of coefficient representation in mathematical functions
USEFUL FOR

Mathematicians, optimization specialists, and students studying linear programming or mathematical optimization techniques will benefit from this discussion.

Bharatisha
Messages
1
Reaction score
0
How to minimise this function and get initial conditions . I have the answer for initial conditions.
ra = min(00237 − 0000175v + 8.693f − 000159y)
subjected to

124.53 ≤ v ≤ 167.03
0.025 ≤ f ≤ 0.083
6.2 ≤ y ≤ 14.8

v= 144.2 , f = 0.025, y = 9.5 How to get this?
 
Physics news on Phys.org
Bharatisha said:
How to minimise this function and get initial conditions . I have the answer for initial conditions.
ra = min(00237 − 0000175v + 8.693f − 000159y)
subjected to

124.53 ≤ v ≤ 167.03
0.025 ≤ f ≤ 0.083
6.2 ≤ y ≤ 14.8

v= 144.2 , f = 0.025, y = 9.5 How to get this?
You can't get this, it is NOT the correct answer.

This is a linear function, defined on a convex set (a rectangular solid, actually). Different values of "ra" represent different planes parallel to one another. If the plane corresponding to a given value of ra passes inside the rectangular solid, we can decrease ra slightly by moving the plane parallel to itself. This is true until the plane passes outside the rectangular solid. It little thought should show you that the last point of the rectangular solid the planes touches will be a vertex (or and entire edge if two vertices give the same value).

So a minimum value for a linear function on a polygonal solve (such as a rectangular solid) must occur at a vertex! Here, it is easy to see that "v= 144.2, f= 0.025, y= 9.5" does NOT give a minimum value because no vertex has "v= 144.2" or "y= 9.5".

(your given function is "00237 − 0000175v + 8.693f − 000159y". What do those coefficients without a decimal point mean? Is "00237" just 237 or .00237 or 0.0237?)
 
Last edited by a moderator:

Similar threads

  • · Replies 8 ·
Replies
8
Views
4K
  • · Replies 16 ·
Replies
16
Views
3K
Replies
4
Views
2K
  • · Replies 7 ·
Replies
7
Views
5K
Replies
10
Views
3K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 3 ·
Replies
3
Views
1K
Replies
4
Views
2K
  • · Replies 12 ·
Replies
12
Views
5K