READ "Input a number: ",num
WRITE !,"the arc tangent is: ",$ZARCTAN(num)
QUIT
WRITE !,"the arc tangent is: ",$ZARCTAN(0.0)
WRITE !,"the arc tangent is: ",$ZARCTAN($DOUBLE(0.0))
WRITE !,"the arc tangent is: ",$ZARCTAN($ZPI)
WRITE !,"the arc tangent is: ",$ZARCTAN($DOUBLE($ZPI))
WRITE !,"the arc tangent is: ",$ZARCTAN($ZPI/2)
WRITE !,"the arc tangent is: ",$ZARCTAN($DOUBLE($ZPI)/2)