Trouble With Simple 'while' Loop Logical Operator

Can't seem to get my while loop to execute.

-No error showing

-Getting rid of 1 initial condition in 'while' loop and the script runs (not how I want though). I need my 'while' loop to accept a number between 1 and 12 (corresponds to 1=Jan, 2=Feb, etc).

Any help with this greatly appreciated!

Script Below:

clear all
clc

M = 100;
Y = -100;

disp('After selecting a month and year, the number of days within that month will be displayed.')

while Y<0
Y = input('Please select a year: ');
end

while (M<0) & (M>12)
M = input('Please select a month: ');
end

Answer 1

[James Kerns]

It would appear you need an OR logical operator in the

while (M<0) & (M>12)

I.e. make it

while (M<0) || (M>12)

[Jan]

Obviously this cannot be true ever: "M lower than 0 and M greater than 12". Frequently reading the source code loud helps to find bugs.

[Dave]

Thanks so much! I thought I went through all the logical operators for the sake of debugging but I guess I didn't. Thanks again :)

[Jan]

Btw., omit the useless clear all: removing all loaded functions from the memory wastes time only. If you really want to clear the variables, use clear variabels.