How to reset typing in loop input if is Negative?

Hello,

I want to make a typo refund if there is a user error with negative. For example if a user types negative then the output will return the same as original.

Thanks for the helpers

clc;          
clear;    
v=input('Insert poisson ratio:'); %Poisson's ratio
if isempty(v) || (v<=0)
end

Answer 1

[Walter Roberson]

while true
    v = input('Insert poisson ratio: '); %Poisson's ratio
    if isnumeric(v) && isscalar(v) && v >= 0
        break
    end
end