Calling multiple outputs of a function into new function

Question

Asim Ismail 2017-5-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/340131-calling-multiple-outputs-of-a-function-into-new-function

评论： Asim Ismail 2017-5-14

采纳的回答： Jan

I have a function with multiple outputs, now i want to call them into a new function and apply some formulas to them.

Applying formulas on each output one by one seems impossible, so any simplest way to do this?

Thanks!

5 个评论
显示 3更早的评论隐藏 3更早的评论

Asim Ismail 2017-5-14

First i made a function

[out1, out2, ....., outn] = fun(in1, in2)

but it didnt give me any output,except the first one, so i removed the function then it gave me a series of outputs (out1, out2, ....., outn) and i start to call them one by one in another function. but this method takes too long, my question is how to avoid this method and use an efficient way.

Jan 2017-5-14

@asim: I see a general problem here. Your explanations are most likely clear, if somebody knows, what you are doing already. But the readers do not have the faintest idea.

Please do not only describe in words, what you are doing, but post the code. This will help us to understand.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Jan 2017-5-14

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/340131-calling-multiple-outputs-of-a-function-into-new-function#answer_266956

在 MATLAB Online 中打开

With some bold guessing:

 [out1, out2, ....., outn] = fun(in1, in2)
 but it didnt give me any output,except the first one,

This might mean, that you define the function as

 function [out1, out2, ....., outn] = fun(in1, in2)
 ...

and call it like this:

fun(in1, in2)

but catching the outputs is obligatory:

[out1, out2, ....., outn] = fun(in1, in2)

Then

i removed the function

might mean, that you removed the top line of the function definition "function [out1, out2, ....., outn] = fun(in1, in2)", such that the code becomes a script. This is a bad idea, because functions are much cleaner and safer. Nevertheless, it might work.

 i start to call them one by one in another function. but this
 method takes too long, my question is how to avoid this method
 and use an efficient way.

I cannot guess, what "call them one by one in another function" means and without seeing the code it is impossible to recognize, why it is taking "too long". Perhaps a pre-allocation is forgotton or teh code can be vectorized, maybe expensive operations are performed repeatedly.

I do not even know what "too long" means - weeks or milliseconds?

So, please, post the code, provide some useful inputs, replace irrelevant input data by radnom arrays and give us a chance to reconsider, what you are doing. Then it will be possible to solve your specific problem.

5 个评论
显示 3更早的评论隐藏 3更早的评论

Stephen23 2017-5-14

编辑：Stephen23 2017-5-14

在 MATLAB Online 中打开

Aha, this seems to be a case of the X-Y problem. Maybe we can finally start to help you. Here is one easy solution to the question you pose in your comment above:

M = [5,3;5,2;2,5;5,3;2,3;3,6]; % the matrix sizes.
R = size(M,1);
C = cell(R,1);
for k = 1:R
    C{k} = rand(M(k,:)); % generate the matrices using those sizes
end

and then you just need to pass one variable C to your next function:

D = cell(size(C));
for k = 1:numel(C)
    D{k} = C{k}>0.5;
end

And D is the output, a cell array of logical arrays, where each logical array shows the conditions that you test for.

Did you see how I just managed to solve your problem by using good program design, in particular I did not try to handle many individual numbered variables (which is very bad program design), but simply put all of the matrices into one cell array. And of course passing one cell array between functions is trivially easy!

Asim Ismail 2017-5-14

Thanks @Stephen, _ Did you see how I just managed to solve your problem by using good program design,_ Thats what i want to do, but i am bit new to matlab, so im learning the things coming to my way and trying to avoid the mistakes in future. Anyway thank you guys for helping me out.

请先登录，再进行评论。