Solve a matrix system generated at runtime

I have a matrix with 31 rows and 4 columns

I want to find the values of unknown parameters a, b, c that multiplied for the other columns minimize the difference between first columns and the rest of the matrix according this formula:

matrix(i,1)=a*matrix(i,2)+b*matrix(i,3)+c*matrix(i,4)+(gam1+gam2*matrix(i,4))

(gam1 and gam2 are 2 constants that I already know, and i is the row index)

Matlab seems doesn't like undefined variables. What is the syntax that I have to use?

Answer 1

[John D'Errico]

abc = matrix(:,2:4)\(matrix(:,1)-gam1-gam2*matrix(:,4));

[Andrew Farsech]

Thanks for the answer. could you clarify me? Doesn't seem work. I need all a, b, c parameters separately.

[John D'Errico]

It honestly does not work? Did you try it? Is it really that difficult to write:

a = abc(1);
b = abc(2);
c = abc(3);

Perhaps it is time to learn how to use vectors in MATLAB?