Error 'Function definition not supported in this context. Create functions in code file.'

Trying to do : function nrm = fournorm(x) for a question

But it comes up with Error: Function definition not supported in this context. Create functions in code file.

[Deepak Gupta]

Where are you trying to do it?

[Mhahida Baksh]

Matlab on command window

[Stephen23]

"Matlab on command window"

Not possible.

Functions may be either:

• defined in a file with the function declaration, or
• defined as an anonymous function.

[Mhahida Baksh]

Im trying to solve a maths question and this is what it tells me to do as the first step:

function nrm = fournorm(x) % find the four-norm of the vector x

[Stephen23]

"...this is what it tells me to do as the first step:"

You need to write that code in a file and save the file using the same name as the function, i.e. fournorm.m.

In MATLAB it is not possible to define functions like that in the command window.

Answer 1

[Srivardhan Gadila]

You have to create functions in files, refer to Create Functions in Files, Add Functions to Scripts & Functions.

If you have simpler functions like

function y = cubicPoly(x)
y = x.^3 + x.^2 + x + 1; 
end

then you can make use of function_handle and define such functions in command window itself or in a script as follows:

f = @(x) x.^3 + x.^2 + x + 1;

[Steven Lord]

To be clearer, you cannot define a function simply by copying and pasting the code starting with the function keyword at the prompt in the MATLAB Command Window. The function keyword is only allowed inside a script, function, or class file.

Answer 2

[Mubbara Muhammad Saleem Sheikh]

function move=tictac(n).         %first computer move in tic-tac-toe. %go for the centre if empty. %otherwise choose the upper left corner.                              if n=5                                  move=5;                            else                              move=1                                end
(Can anyone help me with this.can u tell me why matlab software shows Error: Function definition are not
supported in this context. Functions
can only be created as local or nested
functions in code files.

[Willie Hernandez]

Did you figure it out? I'm having a similar issue.

[Mubbara Muhammad Saleem Sheikh]

Yeah i made a little change in the function

[Shweta Dubey]

what is the change , i got same issue

[Mubbara Muhammad Saleem Sheikh]

Yeah i write function in file "tictac.mm" like this. This is code file

[Mubbara Muhammad Saleem Sheikh]

After this , where we apply function write any value of functions u will get value