function in matlab- undefined input argument error

Question

I can't understand what the problem is with this code. If anyone can help I will be thankful.

function [out] = detj(in1)
%DETJ Summary of this function goes here
%Detailed explanation goes here: N is 2*50 matrix and in1 is scaler
    global N 
    out=(1/8)*(N(1,in1));
end

The error is :

Input argument "in1" is undefined.
Error in ==> detj at 7
out=(1/8)*(N(1,in1));

I defined N in another file

N=importdata('Nodes.txt'); %Matrix of nodes

If you wish to get answer, I would advise to split up the statement where your error is occurring as well as give an example of inputs. I.e, what do in1, in2, in3, in4, N, r, s, look like? How are you calling this function? — Durkee
– Durkee, Commented Jul 27, 2017 at 14:34
As Durkee suggested, add the part of your main script where you call the function detj and where you create N and in1 variables. — marcoresk
– marcoresk, Commented Jul 27, 2017 at 14:48

Marwan Alkhweldi · Accepted Answer · 2017-07-27 15:06:44Z

1

No thing wrong with your code, you just used the function the wrong way.

To use a Function in Matlab you need to call it, NOT to run it directly.

This is your original function code

function [out] = detj(in1,in2,in3,in4)
      %DETJ Summary of this function goes here
      %   Detailed explanation goes here %N is 2*50 Matrix
     global N r s
    out=zeros(2,2);
    for m=1:2
    for n=1:2
     out(m,n)=(1/8)*(((N(1,in1)-N(1,in3))*(N(2,in2)-N(2,in4))-(N(2,in1)-N(2,in3))*(N(1,in2)-N(1,in4)))-r(1,m)*((N(1,in3)-N(1,in4))*(N(2,in1)-N(2,in2))-(N(2,in3)-N(2,in4))*(N(1,in1)-N(1,in2)))+s(1,n)*((N(1,in2)-N(1,in3))*(N(2,in1)-N(2,in4))-(N(2,in2)-N(2,in3))*(N(1,in1)-N(1,in4))));
 end
 end
end

To use your function I tried a simple code,

clc;clear;
global N
global r
global s 
N=ones(2,50);
r=ones(2,2);
s=ones(2,2);
detj(1,2,3,4)

And I got answer as

So no thing wrong with your function, just you need to know how to use it.

Let me know if my answer is not clear else good luck.

answered Jul 27, 2017 at 15:06

Marwan Alkhweldi

1063 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

mh np Over a year ago

my bad, so if we run a function it doesn't matter that we get an error?

Marwan Alkhweldi Over a year ago

Yes exactly, actually I don't see any reason to run a function. Just make sure you save your function every time you make change to it

Collectives™ on Stack Overflow

function in matlab- undefined input argument error

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related