How to add strings to a list

How do I add strings to a list. I used if staements and used the functions append but its not working if one if statement is wrong. I dont know if I need to use a loop.

diagnosistitle = [];
 
x = 1;
y = 1;
z = 1;
 
if x == 1
    str1 = append("X");
end 
 
if y == 1
    str2 = append("Y");
end
 
if z == 2
    str3 = append("Z");
end
 
str = append(str1, str2, str3);

[Adam Danz]

Could you provide examples of the strings you are concatenating?

str1 = 'first'; 
str2 = 'second'; 
str12 = [str1,str2]

% str12 =
%     'firstsecond'

Also, what's the point of "concatenating" a single string?

append("Z")
ans = 
    "Z"

[the cyclist]

It's probably important to distinguish between strings and character arrays here.

Answer 1

[the cyclist]

So, I'm not sure what are really trying to do. But the problem with your specific code is that because this if structure is not entered

if z == 2
    str3 = append("Z");
end

then the variable str3 simply does not exist, when is why the line

str = append(str1, str2, str3);

fails.