how to take a number as input

I am, writing a code in which the user is aked to input a value. the value should be restricted to numbers only and no string. if the user enters anything other than a number error message should be displayed

Answer 1

[Adam Danz]

You can create an input dialog box using answer = inputdlg(prompt,dlgtitle) (see that page for additional input options). The output will be a cell array of characters (or an empty cell array).

Convert the output to numeric

answerNum = str2double(answer); 

Use a conditional error enforcing numeric input

if isempty(answerNum) || isnan(answerNum) % || ~isnumeric(answerNum)
    error('Input must be numeric.')
end

[Stephen23]

isnumeric(answerNum): when is the output of str2double not numeric?

[Adam Danz]

Good point. That last condition is unnecessary. It is leftover from a different idea I initially had.