using for loop plotting problem help me

조회 수: 3 (최근 30일)
ataberk kaplica
ataberk kaplica 2021년 1월 12일
댓글: Rik 2021년 1월 12일
function homework
f= @(x) 3*x^5+7*sind(x)^2;
fd= @(x) 15*x^4+7*sind(2*x)^2+3*x^5+7*sind(x)^2;
a=-1;
b=3;
n=5;
e=1.1*10^3;
s=(fd(a)+fd(b));
for i=1:1:n-1
h=(b-a)/i;
s=s+2*fd(i);
I=(h/2).*s
error=I-e
end
end
the problem is ı have values but try everything for plotting but see nothing even there is no line or spline .
  댓글 수: 3
ataberk kaplica
ataberk kaplica 2021년 1월 12일
i did all plot type , but get nothing
Rik
Rik 2021년 1월 12일
This time I edited your question for you (also removing most blank lines). Next time, please use the tools explained on this page to make your question more readable.
I don't understand your comment. Your function does not contain any plotting functions, and at the end of a function all variables that aren't output variables will be wiped.
Also, you overwrite the contents of you variables every iteration of your loop. You may also want to look at the Onramp part concerning loops and indexing.

댓글을 달려면 로그인하십시오.

채택된 답변

Mathieu NOE
Mathieu NOE 2021년 1월 12일
hello
I assumed that you wanted to plot I and error , but you forgot to index thos variables
see below :
f= @(x) 3*x^5+7*sind(x)^2;
fd= @(x) 15*x^4+7*sind(2*x)^2+3*x^5+7*sind(x)^2;
a=-1;
b=3;
n=5;
e=1.1*10^3;
s=(fd(a)+fd(b));
for i=1:1:n-1
h=(b-a)/i;
s=s+2*fd(i);
I(i)=(h/2).*s;
error(i)=I(i)-e;
end
figure(1),plot(1:n-1,I,'b')
figure(2),plot(1:n-1,error,'r')
  댓글 수: 6
Mathieu NOE
Mathieu NOE 2021년 1월 12일
you're welcome !
Rik
Rik 2021년 1월 12일
Just a note: you should avoid using function names as variable names. It is very common to want to use the error function, so shadowing it is a bad habit (similar to max, mean, and sum).

댓글을 달려면 로그인하십시오.

추가 답변 (1개)

David Hill
David Hill 2021년 1월 12일
What are you trying to plot?
f= @(x) 3*x.^5+7*sin(x).^2;%I doubt you want sind
fd= @(x) 15*x.^4+7*sin(2*x).^2+3*x.^5+7*sin(x).^2;
x=-1:.01:3;
plot(x,f(x),x,fd(x));
  댓글 수: 1
ataberk kaplica
ataberk kaplica 2021년 1월 12일
I am trying to error vs h graph for n 1-10 range

댓글을 달려면 로그인하십시오.

카테고리

Help CenterFile Exchange에서 Loops and Conditional Statements에 대해 자세히 알아보기

제품


릴리스

R2020b

Community Treasure Hunt

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

Start Hunting!

Translated by