Filter löschen
Filter löschen

could i get help with this question?

2 Ansichten (letzte 30 Tage)
poppy
poppy am 25 Nov. 2022
Bearbeitet: Walter Roberson am 26 Nov. 2022
can someone help me with this?
  4 Kommentare
poppy
poppy am 25 Nov. 2022
Bearbeitet: Walter Roberson am 26 Nov. 2022
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.
Walter Roberson
Walter Roberson am 26 Nov. 2022
Bearbeitet: Walter Roberson am 26 Nov. 2022
See diag and blkdiag
Nothing in the assignment calls for integration.

Melden Sie sich an, um zu kommentieren.

Antworten (0)

Kategorien

Mehr zu Loops and Conditional Statements finden Sie in Help Center und File Exchange

Tags

Produkte


Version

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by