I am confused with scalars!!!

if mi(:)>(a1(:)+n(:)) && mi(:)<(a1(:)-n(:)) && (ma(:)>(b1(:)+n(:)) && ma<(b1(:)-n(:))
  boxing_out=all(1);                                     
else if mi(:)>(a2(:)+n(:))&&mi(:)<(a2(:)-n(:))&&ma(:)>(b2(:)+n(:))&&ma(:)<(b2(:)-n(:))
        boxing_out(:)=2;                                  
    else if mi(:)>(a3(:)+n(:))&&mi(:)<(a3(:)-n(:))&&ma(:)>(b3(:)+n(:))&&ma(:)<(b3(:)-n(:))
            boxing_out(:)=3;                              
        else if mi>(a4+n)&&mi<(a4-n)&&ma>(b4+n)&&ma<(b4-n)
                boxing_out(:)=4;                          
            else if mi>(a5+n)&&mi<(a5-n)&&ma>(b5+n)&&ma<(b5-n)
                    boxing_out(:)=5;                      
                else
                    boxing_out(:)=0;                     
                end
            end
        end
    end
end

I write this but I get the follow error. Expected a scalar. Non-scalars are not supported in IF or WHILE statements, or with logical operators. Instead, use ALL to convert matrix logicals to their scalar equivalents. I don't how to solve this question.Who can help me .

[EDITED, Jan, please format your code]

Answer 1

[Roger Stafford]

Apparently your variables 'mi', 'ma', 'a1', 'b1', ..., are arrays with more than one element - that is, they are not scalars. Consequently you cannot use the "short-circuit" logical operators "&&" and "||" with them. Remember, if a variable 'v' is not a scalar, then neither is 'v(:)'.

Also if you use the 'if' function on a logical vector as you seem to have done, it can only come true if all that vector's elements are simultaneously true in the accompanying expression. I suspect that is not what you intended here.

One further observation. You will find it more convenient to use the 'elseif' construct rather than using separate 'else' and 'if' functions.

One more added observation: Rather than

   x > y+z & x < y-z

you can use the equivalent

   -z > abs(x-y)

[mark liang]

Thank you, I will try.谢谢！