how to write a tri diagonal solver in matlab

To solve a tridiagonal system of equations in MATLAB, you can use the "tridiag" function in the "Toeplitz" package. Here's an example code:

main.m
% define the tridiagonal matrix
n = 5; % number of equations
a = diag(ones(n,1)*-1, -1) + diag(ones(n,1)*2) + diag(ones(n,1)*-1, 1);

% define the right-hand side
b = [1;2;3;4;5];

% solve the system
x = tridiag(a,b);

% display the solution
disp(x);
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In this code, we first define the tridiagonal matrix using the "diag" function to set the main diagonal to 2 and the two off-diagonals to -1. Then, we define the right-hand side vector and use the "tridiag" function to solve the system. Finally, we display the solution.