How to output optional variables in a function call?

Hi, I have a function where i want to either output a, b OR c given my input condition which is found in num.

I am getting an error. Output argument "b" (and maybe others) not assigned during call.

Can you please suggest a solution!

For example,

if num=2, i want to output a=10, b=5 and if num=4, i want to output c=100

if true

function [a,b,c] = trial_function(num)

if num==2

a=10; b=5

else if num==4

c=100;

end

end

    end

[Walter Roberson]

duplicates http://uk.mathworks.com/matlabcentral/answers/223808-how-to-output-optional-variables-in-a-function