Problem with using && operator in if conditional statement with array involved

i want to use if statement such that if ((x_value==645:650||730:735||815:820||900:905||980:985||1070:1075||1155:1160||1240:1145||1325:1330||1410:1415||1495:1500||1580:1585)&&(y_value==225:230)) out= S(1); end

OR

xx=[645:650,730:735,815:820,900:905,985:990,1070:1075,1155:1160,1240:1245,1325:1330,1410:1415,1495:1500,1580:1585]; yy=[225:230;275:280;325:330;375:380];

if ((x_value==xx)&& y_value==(yy(1,:))) out=S(1) end

but it gives error

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

what is wrong with my code ??

Answer 1

[Steven Lord]

Use ISMEMBER to check if x_value is an element of your set of desired outcomes.

x = 5;
if ismember(x, [1 3 5 7 9])
  disp('First trial, odd number less than 10!');
end

x = 2;
if ismember(x, [1 3 5 7 9])
  disp('Second trial, odd number less than 10!');
end

Answer 2

[MHN]

You should use one "&" if you have logical vectors.

% Correct
  a = [1,2];
  b = [3,4];
  if a==a & b==b
     c=1;
  end

the following code is wrong:

% Wrong
    a = [1,2];
    b = [3,4];
    if a==a && b==b
       c=1;
    end

[MHN]

The symbols & and && perform different operations in the MATLAB® software. The element-wise AND operator is &. The short-circuit AND operator is && (Matlab documentation). Read more here : http://www.mathworks.com/help/matlab/ref/and.html

[Asad Ullah]

i am using this in a loop and with single & symbol it always skips first if conditions

              if any(xx)==x_value & any(yy(1,:))==y_value
               out=   S(1);
              elseif (x_value==648||733||818||903||988||1073||1158||1243||1328||1413||1498||1583)&&(y_value==278)
               out=   S(2);
              elseif (x_value==648||733||818||903||988||1073||1158||1243||1328||1413||1498||1583)&&(y_value==328)
               out=   S(3);
              elseif (x_value==648||733||818||903||988||1073||1158||1243||1328||1413||1498||1583)&&(y_value==378)
                 out= S(4);
              end

[MHN]

Because you are using "any" in a wrong way:

any: True if any element of a vector is a nonzero number or is
    logical 1 (TRUE)

so the result of any(xx) is always 1 based on your xx vector. And one is not equal to your x_value. What do you want to do in your first statement?