how to write functions in an m-file?

117 views (last 30 days)
learner
learner on 16 Jul 2015
Answered: Image Analyst on 16 Jul 2015
If I define a function like
function (cost) = objective (time)
cost = some non linear equation in time
It shows error in line-1 input argument that is at '(time)'. Please help me how to write a function?
Also, if my function depends on two variables say t1 and t2, how to define it? I've tried using
function (cost) = objective (t1 t2)
and also tried this:
time = [t1 t2]
function (cost) = objective (time)
But it shows error.
  3 Comments
learner
learner on 16 Jul 2015
Edited: Walter Roberson on 16 Jul 2015
Thanks GopalKrishnan, but it's typo in my question. earlier I've tried
function [ f ] = fun1(x)
x=[2 3 4]
And it worked fine for me but in other file, I've written:
function [ cost ] = objective( time )
time=[t1 T]
Also I tried
function [ cost ] = objective( t1 T )
Or
function [ cost ] = objective( t )
t=[t1 T]
But every time it showed an error. I am unable to identify, what went wrong.
Please help.
Walter Roberson
Walter Roberson on 16 Jul 2015
Please copy the entire text of the error message.

Sign in to comment.

Answers (3)

chef13
chef13 on 16 Jul 2015
You should write something like that:
function [ cost ] = objective( time )
%UNTITLED Summary of this function goes here
% Detailed explanation goes here
% Here you put what your function does
end
I hope it helps you.

Ellison Castro
Ellison Castro on 16 Jul 2015
I think it should be constructed like this:
function[output1, output2, ...] = function_name(input1, input2, ...)
% Insert your main code here using your inputs and returning outputs.
end;
You should also remove this line of code if you're using it at the beginning.
clear; clc; clf;
The first line of the m-file must be the function syntax. To call the function, create another m-file using this syntax:
[variable1, variable2, ...] = function_name(value1, value2, ...)
Your number of inputs should be equal to your specified inputs on your function's m-file.
  1 Comment
chef13
chef13 on 16 Jul 2015
Edited: chef13 on 16 Jul 2015
Don't put the semicolomn after the end , it is not needed.

Sign in to comment.


Image Analyst
Image Analyst on 16 Jul 2015
time is a built-in function. Use another name for it, like myTimes.

Tags

No tags entered yet.

Community Treasure Hunt

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

Start Hunting!