Error using gmres. Too many output arguments.

3 次查看（过去 30 天）
Hmm!
Hmm! 2021-11-25
回答： Hmm! 2021-11-26
I am pretty sure about this code that it is working I copied it from a textbook. But when I run it I get the error
"Error using gmres. Too many output arguments." I did all I could but I couldn't able to fix the problem, I think the reason being that I am not strong in matlab coding. Help needed.
clear
m=200;A=2*eye(m)+0.5*randn(m)/sqrt(m);b=ones(m,1);
[x,flag,relres,iter,resvec]=gmres(A,b);
figure(1)
plot(eig(A),'o');
hold on;
x=(1.5:0.001:2.5);
plot(x,sqrt(0.25-(x-2).^2),'r',x,-sqrt(0.25-(x-2).^2),'r');
legend('eigenvalues of A','(x-2)^2+y^2=1/4')
figure(2)
n=1:length(resvec);
semilogy(n,resvec);
hold on;
semilogy(n,4.^(-n),'r');
legend('||r^n||/||b||','4^{-n}');
hold off

请先登录，再回答此问题。

采纳的回答

Hmm!
Hmm! 2021-11-26
Yes. The resolution is that I had another file in the path folder with gmres so removing that file to a different folder did the magic. Thanks ot @Christine Tobler for the insight.

更多回答（1 个）

Yongjian Feng
Yongjian Feng 2021-11-25
It is working, at least for 2021a. Which version are you using please?
When matlab outputs an error, it normally tells you which line as well. Does it say line 3?
  2 个评论
Hmm!
Hmm! 2021-11-25
I am using MATLAB Version: 9.7.0.1261785 (R2019b) Update 3. It didn't tell me the line but when I run the code line by line, the error begins at
[x,flag,relres,iter,resvec]=gmres(A,b);
Christine Tobler
Christine Tobler 2021-11-25
Perhaps you have another file called gmres.m on the path, which overrides the standard one?
Try
which -all gmres
this should list any additional gmres.m that MATLAB might try to call here.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Loops and Conditional Statements 的更多信息

标签

产品


版本

R2019b

Community Treasure Hunt

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

Start Hunting!

Translated by