How do I use inputdlg in a for loop to return a numerical array?

I need to make a program that asks the user how many floors there are and then input each floors dimensions in sequence and then store them in a numerical array for use later but I'm very new to this and struggling somewhat! The contentws of the for loop work fine outside the loop.

floors=inputdlg('enter number of floors: ');
for i=1:1:floors
    dimensions={'Enter height','Enter width:','Enter length:'};
    dlgtitle='Dimensions';
    dims=[1 35];
    answer=inputdlg(dimensions,dlgtitle,dims);
    height(i)=str2num(answer{1});
    width(i)=str2num(answer{2});
    length(i)=str2num(answer{3});
end

[Rik]

I'm on mobile so I can't test your code, but I already see a potential source of issues: you're shadowing the internal function length() with a variable. You are also using str2num instead of the recommended str2double (which avoids an internal call to eval() with all the potential side effects).

[Gregory Hind]

No problem, I converted the floors input to numerical using a str2double and now it works perfectly. What does shadowing the internal function mean? Thanks!

floors=inputdlg('enter number of floors: ');
floors=str2double(floors);
    
for i=1:1:floors
    
    dimensions(i)={'Enter height','Enter width:','Enter length:'};
    dlgtitle='Dimensions';
    dims=[1 35];
    answer=inputdlg(dimensions,dlgtitle,dims);
    height(i)=str2num(answer{1});
    width(i)=str2num(answer{2});
    length(i)=str2num(answer{3});
end

Answer 1

[Rik]

A few good practice tips:

• avoid i and j as variable names to avoid confusion with sqrt(-1), avoid l (lowercase L) as well to avoid confusion with the numeral 1.
• put all code that does not depend on your loop index outside of your loop so it is executed only once
• don't use variable name like sum or length, as that will prevent you from using the internal functions with that name (this is called 'shadowing' of a function)
• pay attention to the warnings mlint is giving you, try to resolve all warnings. If you are certain the warning doesn't apply in your case (which is rare), right-click the orange line and select the 'suppress warning on this line' option.

So here is your code with those tips applied:

n_floors=inputdlg('enter number of floors: ');
n_floors=str2double(n_floors);

dimensions={'Enter height','Enter width:','Enter length:'};
dlgtitle='Dimensions';
dims=[1 35];

height=zeros(1,n_floors);
width=zeros(1,n_floors);
len=zeros(1,n_floors);%you could consider depth as a variable name
for floor=1:n_floors
    answer=inputdlg(dimensions,dlgtitle,dims);
    height(floor)=str2double(answer{1});
    width(floor)=str2double(answer{2});
    len(floor)=str2double(answer{3});
end

[Gregory Hind]

That's excellent info, thank you very much