how to solve a equation

2 visualizzazioni (ultimi 30 giorni)
hua
hua il 14 Dic 2013
Commentato: Walter Roberson il 15 Dic 2013
I have a cell array,its elements are all of expression with symbol variables a{i,j}.
for example
cell array:f{n},
*f{1} = 3*b{3,5}*b{1,2} + 4*b{2,2} + ...+b{i,j},
f{2} = 4*b{3,5} + 4*b{6,2}*b{1,1} + ...+, ;
f{n} = b{2,3} + b{7,8} +;
f{n} = 0;*
I know every .expression of f{i},
if I use fsolve function,I have to display all equations,for large i, it is impractical. so is there any other method to get every b{i,j}'s value ,
can i use fsolve like these fsolve(f);
thank you!!
  3 Commenti
hua
hua il 15 Dic 2013
I dont't want to write down every expressions,
for example,the number of equation exceeds 100
Walter Roberson
Walter Roberson il 15 Dic 2013
What form do you have them available in?

Accedi per commentare.

Risposta accettata

Matt J
Matt J il 14 Dic 2013
Modificato: Matt J il 14 Dic 2013
if I use fsolve function,I have to display all equations,for large i, it is impractical.
You should be using vectorized commands to generate f, not scalar expressions. For example, if I had equations
f(1)=x(1)+1
f(2)=x(2)+2
f(3)=x(3)+3
...
f(N)=x(N)+N
I would generate f in the single statement,
f=x+1:length(x)
regardless of the size of N.
  2 Commenti
hua
hua il 15 Dic 2013
thank you for answer.
I mean I had already get every expression of f{i},and I want to solve these equations.
for example use fsolve function,but this means I have to write every equation,and the
number of f{i} is over 100;I don't want write down every equation,how can I solve these
equations?
Matt J
Matt J il 15 Dic 2013
Modificato: Matt J il 15 Dic 2013
but this means I have to write every equation,
No, I already told you that you don't have to. You must look for an alternative matrix/vector valued way of expressing f.
Also, if you already "get every expression", it means you've already written them down, or that you have them in some sort of executable form.

Accedi per commentare.

Più risposte (0)

Categorie

Scopri di più su Loops and Conditional Statements in Help Center e File Exchange

Community Treasure Hunt

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

Start Hunting!

Translated by