Use trapezoidal method to find the deflection at each measurement point.

3 次查看（过去 30 天）
Sean Flanagan
Sean Flanagan 2022-9-30
编辑： Torsten 2022-10-1
Hi,
I have the following 21x2 matrix
I need to use loops and trapezoidal method to find the deflection at each measurement point. By using the trapz command I can find the overall result but I need guidance with how to find the deflection at each measurement point.
  1 个评论
Sean Flanagan
Sean Flanagan 2022-10-1
cumtrapz gives me each answer for [f(x0)...f(x20]. Is there a way to write the code to give [f(x0)+f(x1)] = ans, [f(x0)+f(x1)+f(x2)] = ans, [f(x0)+f(x1)+f(x2)+f(x3)] = ans .....[f(x0)+f(x1)....+f(x19)+f(x20)] = ans, using for loops?

请先登录，再进行评论。

请先登录，再回答此问题。

回答（1 个）

James Tursa
James Tursa 2022-9-30
Sounds like you want the cumtrapz( ) function. If the assignment requires you to use loops, just code up the formula found in the trapz( ) doc:
https://www.mathworks.com/help/matlab/ref/trapz.html
  4 个评论
显示 2更早的评论
Torsten
Torsten 2022-10-1
编辑：Torsten 2022-10-1
Why
[f(x0)+f(x1)] = ans,
[f(x0)+f(x1)+f(x2)] = ans,
[f(x0)+f(x1)+f(x2)+f(x3)] = ans
.....
[f(x0)+f(x1)....+f(x19)+f(x20)] = ans ?
Don't you need
[f(x0)+f(x1)]/2 * (x1-x0) = ans
[f(x0)+f(x1)] / 2 *(x1-x0) + [f(x1)+f(x2)]/2 * (x2-x1) = ans,
[f(x0)+f(x1)] / 2 *(x1-x0) + [f(x1)+f(x2)]/2 * (x2-x1) + [f(x2)+f(x3)]/2 * (x3-x2) = ans
...
[f(x0)+f(x1)] / 2 *(x1-x0) + [f(x1)+f(x2)]/2 * (x2-x1) + [f(x2)+f(x3)]/2 * (x3-x2) + ... + [f(x19) + f(x20)]/2 * (x20-x19) = ans
?
That's what cumtrapz does.
Otherwise, use cumsum(f) instead of cumtrapz(x,f).

请先登录，再进行评论。

类别

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

标签

产品


版本

R2022a

Community Treasure Hunt

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

Start Hunting!

Translated by