Getting multiple outputs from a function?

Hi everyone. This is my code. It works well in this state but i want to change ''ord'' number from 1 to 4 and ''sfn'' number from 1 to ord+1. For example, when ord=3, sfn values should be 1, 2, 3 and 4, accordingly. How can i do this?

% shapefun( ord,sfn,x ) function gives the value of the 'sfn'th shape function of
% element with order 'order' at x coordinate.
% 'order' can be any integer above 0
% x € [-1,1]
% sfn is integers from 1 up to (order+1),
function result = shapefun(ord,sfn,x)
result=1;
if nargin==0
    ord = 1;
    sfn = 1;
    x = linspace(-1,1,1000);
end
for i = 1:ord+1
    if(i==sfn)
        result = result.*1;
    else
        result = result.*(x-((i-1).*1./ord))./(((sfn-1).*1./ord)-((i-1).*1./ord));
    end
end 
end

[Guillaume]

Your code:

    if(i==sfn)
        result = result.*1;

Last I checked, multiplying by 1 doesn't do much. What is the point of that?

Answer 1

[Anish Navalgund]

Hi Isa,

You can use switch statements to control your order and for each order you can have for loops to calculate for each sfn.

The psuedo code is below.

order = input('order= ');

switch order
    case 1
        for sfn = 1:2
            result = shapefun(ord,sfn,x);
        end
    case 2
        for sfn = 1:3
            result = shapefun(ord,sfn,x);
        end
end

And so on...

Hope this helps.

[Stephen23]

Simpler code does the same thing with much less effort:

for sfn = 1:order+1
    result = shapefun(ord,sfn,x);
end

[Stephen23]

isa karaca's "Answer" moved here:

Anish Navalgund Thanks for answering but where exactly should i put your part into my code? Can you show that pls because i got 'not enough input' warning.

function result = shapefunn(ord,sfn,x)
result=1;
if nargin==0
x = linspace(-1,1,1000);
order = input('order= ');
switch order
    case 1
        for sfn = 1:2
            result = shapefunn(ord,sfn,x);          
        end
    case 2
        for sfn = 1:3
            result = shapefunn(ord,sfn,x);         
        end
end
end
for i = 1:ord+1
    if(i~=sfn)
        result = result.*(x-((i-1).*1./ord))./(((sfn-1).*1./ord)-((i-1).*1./ord));
    end
end 
end

[Stephen23]

@isa karaca: Anish Navalgund showed you a (rather complex) way of calling your function in a loop. They did not show you anything to "put into" your code.

Do you see these (repeated) lines in Anish Navalgund's code?:

result = shapefun(ord,sfn,x);

Those lines call your function. There is nothing here that gets "put into" your function.

[isa karaca]

I got it. I integrate that part into my code but i have another question. For example, when ord=1 and sfn= 1:2, my result matrix is being one row not two, i mean function take sfn as only 2 not both 1 and 2. Can you help about this case?

[Stephen23]

"...my result matrix is being one row not two, i mean function take sfn as only 2 not both 1 and 2. Can you help about this case?"

Most likely you will need to use indexing on the output array, otherwise you simply discard the results of every iteration except for the last one. I say "most likely" as I do not understand your algorithm.

[Anish Navalgund]

@Isa, like @Stephen said you can use his method as the repetition of calling of the function is reduced. :)