could i get help with this question?

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poppy 2022-11-25

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编辑： Walter Roberson 2022-11-26

can someone help me with this?

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poppy 2022-11-25

编辑：Walter Roberson 2022-11-26

在 MATLAB Online 中打开

FIRST Function for Gauss elimination:

function [x, A, b] = GE(A, b)
%-------------------------------------------------------------------------%
%GaussE: Function which performs Gauss Elimination, pivoting if required.
%INPUTS
% A = Input A matrix
% b = Input b vector
%OUTPUTS
% A   = The forward eliminated coefficient matrix
% b   = The forward eliminated b vector 
% x   = The final solution vector x 
%-------------------------------------------------------------------------%    
n = length(A); 
%-------------------------------------------------------------------------%
% FORWARD ELIMINATION START: 
%-------------------------------------------------------------------------%
for i = 1:(n-1)     % Pivot row index (stop at 2nd last row)
    %-------------------------------------------------------------------------%
    % < INSERT PARTIAL PIVOTING CODE HERE > 
    %-------------------------------------------------------------------------%
    for k = (i+1):n                             % Skips the pivot element and indexes what is BELOW it in the SAME COLUMN as the pivot element.
        factor = ( A(k,i) / A(i,i) );           % Calculates the row factor for current row
        for j = 1:n                             % Column index
            A(k,j) = A(k,j) - factor*A(i,j);    % Row subtraction, element-by-element
        end
        b(k) = b(k) - factor*b(i);              % Updates b   
    end
end
%-------------------------------------------------------------------------%
% FORWARD ELIMINATION END
%-------------------------------------------------------------------------%
%-------------------------------------------------------------------------%
% BACKWARDS SUBSTITUTION START: 
%-------------------------------------------------------------------------%
x = zeros(n,1);
x(n) = b(n) / A(n,n);                % Compute x(n) immediately 
for i = (n-1):(-1):(1)               % Row index, starting at the 2nd last row and working backwards
    summ = b(i);
    for j = (i+1):n                  % Before solving for x(i), need to subtract all terms to the RIGHT of the current pivot element (if any). 
        summ = summ - A(i,j)*x(j);   
    end
    x(i) = summ/A(i,i);             % Divide final 'sum' by the pivot element
    x
end
%-------------------------------------------------------------------------%
% BACKWARDS SUBSTITUTION END
%-------------------------------------------------------------------------%
end

Second function:

function [x]=BlockDiagonalSolver(A,b)
n=length(A); 
d=sqrt(length(A));
x=zeros(n,1); 
for i= 1:d 
    start_row=((i-1)*d+1);     
    end_row=(i*d);     
    h=start_row:end_row; 
    
    A_solve=A(h,h);     
    b_solve=b(h); 
    
    [A_1,b_1,x(h)]= GaussE(A_solve,b_solve);  
end

QUESTION: How would I go about generating a d block diagonal system for d = [ 5,10,15....50] and solve each system by integrating the two functions above.