Using logical operators within if statement

This probably is a very silly thing, but somehow I am not getting it right.

I need to input the value of a variable'um' from user. The value should lie within 0<um<1 to be acceptable, else has to be rejected. This is my program :

um=input('um(Between 0 and 1) =');
if um<0 & um>1
    um=0;
    disp('Enter a valid value');
end

If I try the two conditional statements i.e um<0 and um>1 individually , it works. However, using both the statements together, is accepting values of um greater than 1 as well.

I have tried all possible 'if' statements here, i.e :

if um<0 & um>1

if (um<0) & (um>1)

if (um<0) && (um>1)

if (um<0 && um>1)

Nothing seems to work out. I have done thins in C++ numerous times, but there is some problem with my syntax in MATLAB I guess.

Thanks in advance! :)

Answer 1

[Wayne King]

You don't want an &, you want an or |

um=input('um(Between 0 and 1) =');
  if (um<0 || um>1)

        disp('Enter a valid value');
    end

How can something be less than 0 and greater than 1? That should be the same in C++.

[Image Analyst]

Or

uiwait(warndlg('Please enter a value between 0 and 1'));

[Abhivyakti]

Thankyou soo much :)

Answer 2

[Amit]

I think you need to use or (||) .. instead of &

Answer 3

[Andrei Bobrov]

while true
    um=input('um(Between 0 and 1) =');
    if um<0 || um>1
        disp('Enter a valid value');
    else
        break;
    end
end