Error when calling function, "Invalid expression..."

15 次查看（过去 30 天）
Jordan Chancellor
评论： Jordan Chancellor 2019-2-9
I am trying to write a code to perform Gauss Elimination on any [nxn] sized matrix, but am having trouble with my back substitution after getting my matrix into row echelon form. I keep getting the error, "Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters." on line 35 (the line with the symsum function). I am not familiar with Matlab at all, and so also do not know how to get the output of my function. Any help would be appreciated!
function X = GaussElim(A,b)
[m,n] = size(A)
aug = [A,b]
for k = 1:n+1
m = k
for j = k+1:n
if abs(aug(m,k)) < abs(aug(j,k))
m = j
end
if aug(m,k) == 0
fprintf('No unique solution exists.')
break
else
aug([k m],:) = aug([m k],:)
if aug(n,n) == 0
fprintf('No unique solution exists.')
break
else
for j = k+1:n
M(j,k) = aug(j,k)/aug(k,k)
for p = k:n+1
aug(j,p) = aug(j,p)-(M(j,k)*aug(k,p))
end
end
end
end
end
end
x(n) = (A(n,n+1))/(A(n,n))
for i = n-1:1
x(i) = (1/A(i,i))(A(i,n+1) - symsum((A(i,j)*x(j)), j, [i+1, n]))
end
x(j) = x
end
A = [3.4, -6.12, -2.72; -0.5, 1.80, 0.80; 2, -4.86, 2.16;]
b = [0;2;1]
x = GaussElim(A,b)

请先登录，再回答此问题。

回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Linear Algebra 的更多信息

标签

产品


版本

R2018b

Community Treasure Hunt

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

Start Hunting!

Translated by