# Logical Operators

The logical operators for AND (&&) and OR (||) are used to combine simple relational statements into more complex expressions. The NOT (!) operator is used to negate a boolean statement.

``````/**
* Logical Operators.
*
* The logical operators for AND (&&) and OR (||) are used to
* combine simple relational statements into more complex expressions.
* The NOT (!) operator is used to negate a boolean statement.
*/

size(640, 360);
background(126);

boolean test = false;

for (int i = 5; i <= height; i += 5) {
// Logical AND
stroke(0);
if((i > 35) && (i < 100)) {
line(width/4, i, width/2, i);
test = false;
}

// Logical OR
stroke(76);
if ((i <= 35) || (i >= 100)) {
line(width/2, i, width, i);
test = true;
}

// Testing if a boolean value is "true"
// The expression "if(test)" is equivalent to "if(test == true)"
if (test) {
stroke(0);
point(width/3, i);
}

// Testing if a boolean value is "false"
// The expression "if(!test)" is equivalent to "if(test == false)"
if (!test) {
stroke(255);
point(width/4, i);
}
}

``````

This example is for Processing 4+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.