## I would like to get the b value in Matalb.

### Redwood (view profile)

on 16 May 2013

Dear Matlab experts,

I would like to get the b value in Matlab, but I got nothing in Matlab. I attached my coding below. Please let me know how to get the b value.

syms b G G1 M1 M2 M3 P1 P2 P3
b  = 0:.0001:10;
Out=solve(' G1 == G*(P1*exp(-b*M1/P1)/( P1*exp(-b*M1/P1)+ P2*exp(-b*M2/P2) + P3*exp(-b*M3/P3)))', b)
G = [7340, 7194];
G1 = [4516.881,  5002.953];
M1 = [5222.328, 6009.419];
M2 = [3264.034, 2632.621];
M3 = [1264.034, 1632.621];
P1 = [3000, 3025];
P2 = [10000, 10051];
P3 = [5000, 5051];
Out=subs(Out)

Thank you very much in advance.

Sincerely,

Redwood

## Products

No products are associated with this question.

### Walter Roberson (view profile)

on 16 May 2013

Use

syms b

instead of assigning a numeric value to b.

### Redwood (view profile)

on 16 May 2013

Dear Walter,

Thank you very much for your help.

But I did not get anything in Matlab.

Sincerely yours,

Redwood

Walter Roberson

### Walter Roberson (view profile)

on 16 May 2013

Is there reason to expect that there is an algebraic solution? If not then you are going to have to do the substitution first and then do a numeric solution. You will likely have to do each set of values individually rather than the two sets together.

### sami (view profile)

on 16 May 2013

inner matrix must agree

### Redwood (view profile)

on 16 May 2013

Dear Sami,

What do you mean, "inner matrix must agree"?

Sincerely yours,

Redwood

#### Join the 15-year community celebration.

Play games and win prizes!

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi