How to get the coefficients of an equation

4 vues (au cours des 30 derniers jours)
Geovane Gomes
Geovane Gomes le 8 Nov 2023
Dear all,
Is it possible to extract the coefficients of an equantion defined as below:
syms x1 x2
eq = 2*x1 + x2 <= 0
eq = 
By using coeffs and sym2poly did not work when it has the relational operator "<=".
c = coeffs(eq)
c = 
1
c = sym2poly(eq)
Error using sym/sym2poly
Not a polynomial.
  2 commentaires
Dyuman Joshi
Dyuman Joshi le 8 Nov 2023
What is the expected output?
[1 2] or [2 1]? or something else?
Geovane Gomes
Geovane Gomes le 8 Nov 2023
[2 1]

Connectez-vous pour commenter.

Réponse acceptée

Dyuman Joshi
Dyuman Joshi le 8 Nov 2023
How about -
syms x1 x2
eq = 2*x1 + x2 <= 0
eq = 
out = flip(coeffs(lhs(eq)))
out = 
  1 commentaire
Geovane Gomes
Geovane Gomes le 8 Nov 2023
Good solution!
This way I can also have the term in the right side
syms x1 x2
eq = 2*x1 + x2 <= 5
eq = 
out = flip(coeffs(rhs(eq)))
out = 
5
Thanks!

Connectez-vous pour commenter.

Plus de réponses (1)

Sulaymon Eshkabilov
Sulaymon Eshkabilov le 8 Nov 2023
Maybe it is appropriate to work in a reverse order, e.g.:
syms x1 x2
Coeff = [2;1];
eq = [x1, x2]*Coeff<=0
eq = 

Catégories

En savoir plus sur Symbolic Math Toolbox dans Help Center et File Exchange

Tags

Produits


Version

R2023a

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by