Why does the code return an additional answer value that I have not asked for?

First I defined a function:

function [p,q] = quadratic_formula(a, b, c)

p = (-b + sqrt((b)^2-4*a*c))/(2*a)
q = (-b - sqrt((b)^2-4*a*c))/(2*a)

end

After that I called the fuction with varying values. Every time it returns an answer value that I haven't asked for. For example,

quadratic_formula(5, 8, 3)

returns following:

p =

-0.6000

q =

-1

ans =

-0.6000

I don't want this answer value. Why does it return that equal to the value of 'p'?

Answer 1

[Davide Masiello]

That is because you call the function without assigning it to a variable.

Therefore Matlab assigns it to a variable called ans, which can accept only one value, i.e. the first one (or p in your case).

So, the first 2 values that appear are printed from within the function (because you didn't use semicolons).

Then it also shows ans because you also call the function without semicolons.

A better way of doing this in Matlab is

[p,q] = quadratic_formula(5, 8, 3)

p = -0.6000

q = -1

function [p,q] = quadratic_formula(a, b, c)
p = (-b + sqrt((b)^2-4*a*c))/(2*a);
q = (-b - sqrt((b)^2-4*a*c))/(2*a);
end

Answer 2

[Karen Yadira Lliguin León]

you need to put ';' at the end of the line to stop . Change these lines

p = (-b + sqrt((b)^2-4*a*c))/(2*a);
q = (-b - sqrt((b)^2-4*a*c))/(2*a);