How can I use a vector inside an @fun?

Question

Carlos Zúñiga 2019-10-22

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/486896-how-can-i-use-a-vector-inside-an-fun

评论： Carlos Zúñiga 2020-8-31

采纳的回答： Artemio Soto Breceda

Hello everyone,

I want to define a function like "fun = @(x) sin(a*x)" where "a" is a vector of n dimention.

Do you have any idea?

Thank you for your support.

Greetings.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Artemio Soto Breceda 2019-10-22

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/486896-how-can-i-use-a-vector-inside-an-fun#answer_397752

在 MATLAB Online 中打开

I might not be understanding your question properly, but it looks like your code works just fine. Here is an example:

a = linspace(0,2*pi,1000); % Create a vector of dimension N = 1000 with values increasing
                           % linearly from 0 to 2*pi
fun = @(x) sin(a*x);       % Define your function
plot(a, fun(1));           % plot 1 period of the sine wave (from 0 to 2*pi);
hold
plot(a, fun(2));           % x = 2
plot(a, fun(4));           % x = 4

I made a a 1000 elements vector, then used your exact code to define fun, and used the new function with three different inputs. Works perfectly as you wrote it.

2 个评论
显示无隐藏无

Walter Roberson 2019-10-23

I agree, in the context provided, using a vector or matrix inside an anonymous function is not a problem.

The kinds of problems that can arise:

the majority of the time you should use the vector operations such as .* and .^ and ./ instead of * and ^ and /
fzero and the minimizers such as fmincon cannot work with vectors or arrays being returned: gamultiobj is the only minimizer that can work with vectors being returned
integral() can only deal with vectors or arrays being returned if you use the 'arrayvalued' option
integral2() cannot deal with vectors or arrays being returned
if you are using arrayfun() or cellfun() or stuctfun() then you need to use 'uniform', 0 to return non-scalars