Use the map() function to take any number and scale it to a new number that is more useful for the project that you are working on. For example, use the numbers from the mouse position to control the size or color of a shape. In this example, the mouse’s x-coordinate (a number between 0 and 360) is scaled to a new number to define the color and size of a circle. Example ReWritten in Python By: Prabhjot Singh (NITH) example original in Java mode examples: Math->Maps

def setup():
    size(640, 360)
    noStroke()


def draw():
    background(0)

    # Scale the mouseX value from 0 to 640 to a range between 0 and 175
    c = map(mouseX, 0, width, 0, 175)

    # Scale the mouseX value from 0 to 640 to a range between 40 and 300
    d = map(mouseX, 0, width, 40, 300)

    fill(255, c, 0)
    ellipse(width / 2, height / 2, d, d)