Validated Input Function

Like the built-in input function but with the ability to impose constraints and checks on user input

s = VALIDATEDINPUT(prompt,'s',validStrings) will process the input S using s = validatestring(S,validStrings).
k = VALIDATEDINPUT(prompt,classes,attributes) checks the input A using validateattributes(A,classes,attributes).

k = VALIDATEDINPUT(prompt,validationFcn) checks the input using the provided validationFcn.

If the user input provided at the prompt is invalid, the user will be informed of the reason why and re-prompted until a valid input is given.