Error using ~= Matrix dimensions must agree during using while function

I was testing the while loop for my ATM script.

password = 'jjteam'

password =

ucsdmate

balance = num1str(9.5405*100,'%10.2f%')

lastlogindate = datenum(2014,11,2,11,7,39)

lastlogindate =

     7.3591e+05

datestr(lastlogindate)

rate = num2str(0.02*100,'%5.2f%%')

I save above code as atm.mat.

 load ('atm.mat')

inpass = input('Enter your password : ','s');
while inpass ~= mypassword
    disp('The passwoard is wrong,please try again.')
    inpass = input('Enter your password : ','s');
end
fprintf('Your password is right.\n')

However, when I try to test my script, it said Error using ~= Matrix dimensions must agree. And Error in atm ,while inpass ~= mypassword. I am not sure which part I did wrong. Can anyone point it out? Thanks

Answer 1

[Guillaume]

Use strcmp to compare strings. == and ~= will only work if the strings are the same length.

while ~strcmp(inpass, mypassword)
  ...

[jarvan]

thanks for your answer

[Abdul Kazi]

Hi, but what if I wanted it to work despite the strings not being same length?

[Walter Roberson]

If you are using character vectors and you want to be able to use == to compare character vectors that might be different lengths, and you do not want to use strcmp, then you will need to create a new eq() method for the @char class and you will need to ensure that you version is earlier on the MATLAB path than the built-in version.

If you are using R2016b or later, you could use the string data type instead of character vectors, such as

string(inpass) ~= string(mypasswd)

Answer 2

[Julia]

Hi,

I don't see where you use "mypassword". You declare only the string "password".