how to solve a system of equations with n equation and m unknown (m>n)?
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
to solve this equation "f = a+b θs + c θv cos(φ)" : unknowns are : f, a, b & c i am working on space image and can calculate θs, θv & φ for all pixel of image so i can write a lot of equation. and there are 2 constraint :
How do I solve this system of equations?
4 commentaires
Jan
le 25 Juil 2012
Dear nasrin, of course we cannot access the files on your harddisk. Imagine what this would mean!
Réponses (1)
Sargondjani
le 25 Juil 2012
i think fmincon (constrained optimization) will work best... if you try to minimize some error use as the objective: objective=error^2.
if you dont have the optimization toolbox you can try fminsearchcon from the file exchange (but this only works properly for a couple of variables at most)
note that fmincon can only find one local solution and it requires a continuous function + continuous derivate. if not continuous, then you should try genetic algorithm
3 commentaires
Sargondjani
le 31 Juil 2012
fminsearchcon does exist in the 'file exchange', ie. you have to download it.
MJTHDSN
le 12 Avr 2018
Dear Matlabers,
I have a similar question but a little bit confusing. Let`s assume we have 6 equations as below:
EQ1:a{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(L^2)*(T^2)-2*L*(T^2)+ (T^2)-(2*L*T*B)+(T*B)+(B^2)
EQ2: b{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(L^2)*(T^2)+(2*L*T*B)+(B^2)
EQ3: c{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(T^2)+(2*T*B)+(B^2)
EQ4:d{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(L^2)*(T^2)-2*L*(T^2)+ (T^2)-(2*L*T*B)-(T*B)+(B^2)
EQ5: e{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(L^2)*(T^2)-(2*L*T*B)+(B^2)
EQ6: f{{(L^2)*(Z^2)+(L^2)*(M^2)-2*L*(Z^2)+(Z^2)}}=(T^2)-(2*T*B)+(B^2)
in the equations above a,b,c,d,e and f are the numerical known values (0.543 for example). So we have 6 equations with 5 unknowns as L, Z, M, T and B.
Can you please give me cues how to solve the equations to find these unknowns using MATLAB.
Best Regards,
Voir également
Catégories
En savoir plus sur Solver Outputs and Iterative Display 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!