ATN2( ) Function Example

CLEAR
? PI( )  && Displays 3.14
? ATN2(0,-1)  && Displays 3.14
STORE COS(PI( )) TO gnXCoord
STORE SIN(PI( )) TO gnYCoord
? ATN2(gnYCoord,gnXCoord)  && Displays 3.14
? ATN2(gnYCoord,gnXCoord)/PI( )  && Displays 1.00