accessing single function from an array of functions

6 次查看（过去 30 天）
Barbara Margolius
评论： Barbara Margolius 2022-3-4
I have defined a matrix of functions:
a=@(t) (1+0.8*sin(2*pi*t));
b=@(t) .8*(1-0.8*sin(2*pi*t));
z = @(t) 0*t;
%T = matlabFunction(fmat);
T=@(t) [-3*a(t) a(t) a(t) a(t) z(t) z(t);...
a(t) -5*a(t) a(t) a(t) a(t) a(t); ...
a(t) a(t) -5*a(t) a(t) a(t) a(t); ...
b(t) b(t) b(t) -5*b(t) b(t) b(t); ...
b(t) b(t) b(t) b(t) -5*b(t) b(t); ...
a(t) a(t) a(t) b(t) 5*b(t) -3*a(t)-6*b(t)];
If I want to access just a single function from the matrix, how do I do it? I have tried several approaches and keep getting: Error: Invalid array indexing.
  1 个评论
Walter Roberson
Walter Roberson 2022-3-4
See https://www.mathworks.com/matlabcentral/answers/539642-is-it-possible-to-have-an-array-of-function-handles#comment_2020739

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Torsten
Torsten 2022-3-4
编辑：Torsten 2022-3-4
f = {@(t) t, @(t) exp(t), @exp} % the second and third are equivalent
SecondFunction = f{2};
ValueOfSecondFunction = SecondFunction(1)
Does that help ?
  6 个评论
显示 4更早的评论
Torsten
Torsten 2022-3-4
编辑：Torsten 2022-3-4
h=0:.01:.99;
myLTh = arrayfun(myLT,h);
plot(h,myLTh)
But to be honest: I can't decipher what you are doing in your code.

请先登录，再进行评论。

更多回答（1 个）

Voss
Voss 2022-3-4
a = @(t)(1+0.8*sin(2*pi*t));
b = @(t)0.8*(1-0.8*sin(2*pi*t));
z = @(t)0*t;
%T = matlabFunction(fmat);
% T is a function of t which returns a 6-by-6 matrix.
% Each element of T is derived from the outputs of functions a, b, and z,
% which are also functions of t.
T = @(t)[ ...
-3*a(t) a(t) a(t) a(t) z(t) z(t);...
a(t) -5*a(t) a(t) a(t) a(t) a(t); ...
a(t) a(t) -5*a(t) a(t) a(t) a(t); ...
b(t) b(t) b(t) -5*b(t) b(t) b(t); ...
b(t) b(t) b(t) b(t) -5*b(t) b(t); ...
a(t) a(t) a(t) b(t) 5*b(t) -3*a(t)-6*b(t); ...
];
% the 6-by-6 matrix returned from the function T when it is called with
% input 1:
result = T(1)
% get some element of the result (the result is the matrix returned from
% calling the function T with input 1):
result(4,5)
% trying to do the same with the output of the function T called with
% input 1 directly doesn't work in MATLAB (the output from T should be
% stored in a variable first, i.e., 'result' here):
try
T(1)(4,5);
catch ME
disp(ME.message);
% but you can index T(1) without storing in a variable, if you really
% want to:
subsref(T(1),substruct('()',{4,5}))
end

类别

在 Help Center 和 File Exchange 中查找有关 Resizing and Reshaping Matrices 的更多信息

标签

产品


版本

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by