Simpson's 1/3 rules

6 次查看（过去 30 天）
Nasser Yari
Nasser Yari 2016-3-31
编辑： Walter Roberson 2016-4-1
Hi,
I am not sure why this does not work.Should I replace the i with j?I appreciate any help.
function I=mysimp(f,a,b,n)
h=(b-a)/n;
sum4=0;
sum2=0;
for i=2:2:n
x(i)=a+i*h;
y(i)=f(x(i))
sum4=sum4+4*feval(f,x(i));
end
if i=3:2:n-1;
x(i)=a+i*h;
y(i)=f(x(i))
sum2=sum2+2*feval(f,x(i));
end
sum=sum2+sum4+feval(f,a)+feval(f,b);
I=sum*h/3;
plot(x,y)
this is what I get
Error: File: mysimp.m Line: 10 Column: 9
The expression to the left of the equals sign is not a valid target for an assignment.

请先登录，再回答此问题。

采纳的回答

John D'Errico
John D'Errico 2016-3-31
A TERRIBLE idea to use the name sum as a variable. You WILL get int trouble later on if you continue to use incredibly useful function names as variable names too. And then your anquished question will be WHAT IS WRONG WITH MY CODE????
Regardless, the following line is not valid syntax in MATLAB:
if i=3:2:n-1;
  1 个评论
Nasser Yari
Nasser Yari 2016-4-1
Thanks for the advice. I found out where I made a typo mistake if should be for.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Numerical Integration and Differential Equations 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by