Issues with reading/using "*" and "#" in a string

I'm building a simple tone dialer for a lab, and I thought it would be cool to evaluate the user's input string into an array, and then evaluate each piece of that array so I can assign it to a sound that plays back to the user. Right now I've successfully been able to read and spit out the string with some accuracy, but when I join "*" or "#" with another number it seems to be messing with the ASCII value because it exits right out of my IF statement. I'll post my code as I have it right now, thanks in advance for any help.

P.S. This is very incomplete, just trying to make sure I can reasonably validate an input

-------------------------------------------------------------------------------------------------------

token1 = 0;
while token1 == 0
    input2 = input('Please enter a 7 digit phone number: ','s');
    [number, token1] = getNumber(input2);
end

----------------------------------------------------------------

function [out2,token] = getNumber(y)
inputNum = num2str(y) - '0';
for i = 1:length(inputNum)
    if inputNum(i) >= 0 & inputNum <= 9 | inputNum == -6 | inputNum == -13 
        switch inputNum(i)
            case 0
                disp(inputNum(i))
            case 1
                disp(inputNum(i))
            case 2
                disp(inputNum(i))
            case 3
                disp(inputNum(i))
            case 4
                disp(inputNum(i))
            case 5
                disp(inputNum(i))
            case 6
                disp(inputNum(i))
            case 7
                disp(inputNum(i))
            case 8
                disp(inputNum(i))
            case 9
                disp(inputNum(i))
            case -6
                fprintf("*%c",newline);
            case -13
                fprintf("#%c",newline);
                
        end
    else
        fprintf("That is not a valid phone number, please enter a valid number.%c",newline);
        token = 0;
        break
    end
    token = 1;
end

out2 = 0;
end

Answer 1

[Dyuman Joshi]

> You only used i-th term for the first comparison only, rest of the comparisons are with vector.

if inputNum(i) >= 0 & inputNum <= 9 | inputNum == -6 | inputNum == -13 

Correct it -

if inputNum(i) >= 0 & inputNum(i) <= 9 | inputNum(i) == -6 | inputNum(i) == -13

And, as you are comparing with discrete values, you can use ismember -

if ismember(inputNum(i), [-6 -13 0:9])

Additionally, you can combine multiple cases which have the same statments -

  switch inputNum(i)
        case {0:9}
            disp(inputNum(i))
        case -6
            fprintf("*%c",newline);
        case -13
            fprintf("#%c",newline);
    
    end 

Also, you might want to check the length on the input as well, if it is 7 digits or not.

[Shawn]

I'm so silly, thank you!

[Shawn]

Also I didn't want to combine multiple cases because each number plays a different tone.

[Dyuman Joshi]

Oh, I guess you have used disp(inputNum(i)) for the cases as an example for now?

[Shawn]

Exactly! I just wanted to make sure that every case was working by itself. I know its a little extra but if I'm absolutely certain about my input then I can safely assume any issues I run into later have nothing to do with input processing.

[Dyuman Joshi]

Yes, that is correct.

Though I will re-iterate one thing - you might want to include a check for the length of the input.

Because, right now, your code runs for an input with other number of digits.

[Voss]

@Shawn: The values checked in your original case statements were correct:

double('0123456789*#' - '0')

ans = 1×12

0 1 2 3 4 5 6 7 8 9 -6 -13

Also, there is no need to use the newline function with fprintf, since the format spec argument to fprintf can contain '\n' to indicate newlines:

fprintf('*\n')

*

fprintf('#\n')

#

Or you could've used disp, as in the other cases:

disp('*')

*

disp('#')

#

And @Dyuman Joshi is correct that you can use a cell array to check for more than one value in a single case statement:

x = 5;
switch x
    case {0:9} % scalar cell array containing the vector 0:9 [doesn't match x=5 because ~isequal(5,0:9)]
        disp('match')
    otherwise
        disp('no match')
end

no match

But in this case it should be a cell array of scalars:

x = 5;
switch x
    case num2cell(0:9) % 1x10 cell array containing scalars 0,1,...,9
        disp('match')
    otherwise
        disp('no match')
end

match