How can I classify a variable if it is a string or a number?

I want to display if the costumer has introduced a number or a string when is requested.

Answer 1

[Benjamin Avants]

Use the class() function.

str = 'Test';
num = 1;

strcmp(class(str),'char')
true

strcmp(class(num),'double')
true

Of course, if the entry was prompted with inputdlg, all responses will be returned as strings. In that case, you'll need to try and convert the string to a number and examine the result. If str2num or str2double can't convert a string, they return NaN.

[Walter Roberson]

str2num() would convert 'pi' to a number...

[Benjamin Avants]

True... so you may want to check for specific cases like that if they are likely to happen. Thankfully, there aren't that many.