MATLAB: SSS Triangle functions, need output help

functionsif statementMATLAB

My function is outputting ang1, ang2, and ang3 in addition to my fprintf statements, why? and how to i fix it? Question asks for my to calculate it the triangle is valid by checking the area.
function [ang1 ang2 ang3 ] = triangle(s1,s2,s3)
%TRIANGLE calculates the degrees of all angles given the length of all

%sides.;

s1=input('Please input side 1: ');
s2=input('Please input side 2: ');
s3=input('Please input side 3: ');
s=(s1+s2+s3)/(2);
Area=sqrt(s*(s-s1)*(s-s2)*(s-s3));
if Area > 0
ang1=acosd((s2^2 + s3^2 - s1^2)/(2*s2*s3));
ang2=acosd((s3^2 + s1^2 - s2^2)/(2*s3*s1));
ang3=acosd((s1^2 + s2^2 - s3^2)/(2*s1*s2));
fprintf('The angle opposite side 1 is %.2f deg\n',ang1);
fprintf('The angle opposite side 2 is %.2f deg\n',ang2);
fprintf('The angle opposite side 3 is %.2f deg\n',ang3);
elseif Area >= 0
fprintf('The 3 sides do NOT form an open triangle!\n');
end
end
I'm also having a problem with triangle inputs (1,2,3), it says the correct thing but outputs an error with it
Error in ==> triangle at 5
s1=input('Please input side 1: ');
??? Output argument "ang1" (and maybe others) not
assigned during call to "P:\triangle.m>triangle".
do the input statements need to be outside the function?
FINAL SOLUTION:
function [ang1 ang2 ang3]=triangle(s1,s2,s3)
%TRIANGLE calculates the degrees of all angles given the length of all
%sides.;
ang1=acosd((s2^2 + s3^2 - s1^2)/(2*s2*s3));
ang2=acosd((s3^2 + s1^2 - s2^2)/(2*s3*s1));
ang3=acosd((s1^2 + s2^2 - s3^2)/(2*s1*s2));
end
%Test_triangle
s1=input('Please input side 1: ');
s2=input('Please input side 2: ');
s3=input('Please input side 3: ');
s=((s1+s2+s3)/(2));
Area=sqrt(s*(s-s1)*(s-s2)*(s-s3));
if Area > 0
[ang1 ang2 ang3]=triangle(s1,s2,s3);
fprintf('The angle opposite side 1 is %.2f deg.\n',ang1);
fprintf('The angle opposite side 2 is %.2f deg.\n',ang2);
fprintf('The angle opposite side 3 is %.2f deg.\n',ang3);
elseif Area <= 0
fprintf('The 3 sides do NOT form an open triangle!\n');
end

Best Answer

This is because your function defines them as output arguments
function [ang1 ang2 ang3 ] = triangle(s1,s2,s3)
MATLAB expects 3 outputs as defined by ang1,ang2 and ang3. Thats why you get the error.
If you don't want the outputs, just define the function as:
function triangle(s1,s2,s3)