integers to English phrase

I am trying to create a function that converts double digits between 21 and 39 into its english phrase.

I think I have the beginning of the code that sets the integer parameter but I do not know what to do next. This is what I have so far:

function S = Convert_to_words(number)
   ones = {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens = {'', '', 'ERROR', 'Twenty', 'Thirty'};
end

[Walter Roberson]

[tens{tens_digit+1}, ones{ones_digit+1}]

[Britnie Casillas]

When I add this to the function, it says I get an error.

[Matt J]

It is entirely possible that you got an error, depending on what you did to generate tens_digit and ones_digit. But how would we offer advice on that without seeing what you did, and the error message that you got?

[Britnie Casillas]

function S = num2words(number)
   ones_digit = {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens_digit = {'', '', 'ERROR', 'Twenty', 'Thirty'};
   [tens{tens_digit+1}, {ones_digit+1}];
end

when I type it into the command window:

>> num2words(21)
Undefined function or variable 'tens'.
Error in num2words (line 4)
   [tens{tens_digit+1}, {ones_digit+1}]; 

[Matt J]

Well, one problem is that Walter's advice was based on your initial code where tens and ones were (a) provided by you and (b) equal to lists of string that you've now renamed to something else.

   ones= {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens = {'', '', 'ERROR', 'Twenty', 'Thirty'};

In your latest code however, tens and ones are no longer provided, but you still try to use them the same way as in Walter's suggestion. Another problem is that you are not using the input variable number anywhere.

[Britnie Casillas]

So youre saying instead of doing:

function S = num2words(number)
   ones = {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens = {'', '', 'ERROR', 'Twenty', 'Thirty'};
   [tens{tens_digit + 1}, ones{ones_digit + 1}];
end

I should do?

[tens{tens_digit+1}, ones{ones_digit+1}]

[Britnie Casillas]

even when I go back to my original function and add Walters:

function S = convert_to_words(number)
   ones= {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens = {'', '', 'ERROR', 'Twenty', 'Thirty'};

[tens{tens_digits + 1}, ones{ones_digits + 1}];
end

and when i type it into the command window

>> convert_to_words(21)
Undefined function or variable 'tens_digits'.
Error in convert_to_words (line 5)
[tens{tens_digits + 1}, ones{ones_digits + 1}]; 

[Matt J]

Well, the error message is telling you the problem. You haven't created the variables tens_digits or one_digits. You were supposed to derive them from number. That was the piece of your homework that Walter left for you to do.

[Britnie Casillas]

wouldnt the tens_digits and one_digits be the same variables as the ones and tens? What do you mean derive them from number?

[Stephen23]

"wouldnt the tens_digits and one_digits be the same variables as the ones and tens? "

No.

tens ans ones are cell arrays of character vectors.

tens_digits and one_digits should be numeric values of the digits in the given number (which by adding one to (because MATLAB indexing starts from one) can be used as indices into ones and tens).

"What do you mean derive them from number? "

You need to get the digits from number, as numeric values.

Answer 1

[Matt J]

As a further hint, consider the following version, which is almost what you want

function S = convert_to_words(number)
   ones= {'', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'};
   tens = {'','ERROR', 'Twenty-', 'Thirty-'};
   
   tens_digit=3;
   ones_digit=4;
   
 S=[tens{tens_digit + 1}, ones{ones_digit + 1}];
 
end

It works very reliably on the number 34,

>> S=convert_to_words(34)

S =

    'Thirty-Four'

Your job is to get it to work for everything else.

[Britnie Casillas]

Thank you very much

[Walter Roberson]

However 30 exactly is going to output something that ends in a hyphen when it shouldn't.