solving 4 equation with 4 unkowns

2 vues (au cours des 30 derniers jours)
Omar H.
Omar H. le 6 Avr 2020
Commenté : Omar H. le 6 Avr 2020
good evening
i've been trying to solve these 4 equations using fsolve but the error Index exceeds array bounds. Kept appearing.
i've read multiple posts with the same problem but i couldn' solve the problem
is there anything wrong in the equations that i haven't noticed ?
thanks for the help
function F = myfun(x)
F = [
x(4) -135 +x(2);
130*cos(x(1)) - 31.7*cos(x(2)) - 140*cos(x(3)) - 146.4*cos(172.15);
130*sin(x(1)) - 31.7*sin(x(2)) - 140*sin(x(3)) - 146.4*sin(172.15);
-45*cos(x(4)) + 70*cos(x(5)) - 140*cos(x(3)) - 53.85*cos(68.198);
-45*sin(x(4)) + 70*sin(x(5)) - 140*sin(x(3)) - 53.85*sin(68.198);
];
end
  2 commentaires
Lubos Smolik
Lubos Smolik le 6 Avr 2020
Could you also provide your main script? It appears that there are 5 equations in your function.
Omar H.
Omar H. le 6 Avr 2020
thank you for commenting Lubos smolik
i'm a new user and i'm still learning.
i'm trying to solve a problem in one of my classes there are 5 unknowns and 4 equations
r2cos(x1) - r3cos(x2) - r4cos(x3) - r1cos(x10)
r2sin(x1) - r3sin(x2) - r4sin(x3) - r1sin(x10)
r5cos(x4) - r6cos(x5) - r4cos(x3) - r7cos(x11)
r5sin(x4) - r6sin(x5) - r4sin(x3) - r7sin(x11)
Where r2=130 r3=3.7 r4=140 r1=146.4 x10=172.15 r5=45 r6=70 r7=53.85 x11=68.198
and a fifth one between
x(4) = x(2) + 135

Connectez-vous pour commenter.

Réponses (1)

darova
darova le 6 Avr 2020
It's because of the way you concantenate your equations
Example of two different declarations
[1 - 2]
ans =
-1
[1 -2]
ans =
1 -2
Better practice would be:
F = zeros(5,1);
F(1) = x(4) -135 +x(2);
F(2) = 130*cos(x(1)) - 31.7*cos(x(2)) - 140*cos(x(3)) - 146.4*cos(172.15);

Catégories

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

Community Treasure Hunt

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

Start Hunting!

Translated by