Operands to the || and && operators must be convertible to logical scalar values.

I have such kind of simple code. But when I tried to include it in "if else" like below, this command: Operands to the || and && operators must be convertible to logical scalar values, just appears.

prompt1 = {'sth 1:' , 'sth 2:' };
title = 'Front Range';
dims = [1 50] ;
definput = {' ', ' '};
x1 = inputdlg(prompt1,title,dims,definput);

if  ge(x1, 100) || lt(x1, 1)
    return   
else
    prompt2 = {'sth 3:' , 'sth 4:' };
    title2 = 'Post-Range';
    dims2 = [1 50];
    definput2 = {' ',''};
    x2 = inputdlg(prompt1,title2,dims2,definput2);
end

[Rik]

With the debugger enabled, you can try to evaluate the parts of that statement. Both parts should be a logical scalar. Apparently that is currently not the case.

Answer 1

[Walter Roberson]

inputdlg() returns a cell array of character vectors. You need to use str2double(x1) to convert to numeric form. Watch out for nan, which will be returned for empty values or for values that are not valid single numbers.

Answer 2

[Image Analyst]

Try this:

ca = inputdlg(prompt1,  'Front Range', dims, definput);
% ca is a cell array.
sth1 = str2double(ca{1})
sth2 = str2double(ca{2})
if  sth1 < 1 || sth1 > 100 || sth2 < 1 || sth2 > 100
    return;
else........

Don't use title as the name of your variable because that is the name of a built-in function.