// Scilab Code Ex2.4 : Page-47 (2010)
p = 60;    // Power rating of bulb, watt
d = 0.5;    // Distance from the blb, m
P = p/(4*%pi*d^2);    // Value of Poynting vector, watt per metre square
printf("\nThe value of Poynting vector = %4.1f watt per metre square", P);

// Result 
// The value of Poynting vector = 19.1 watt per metre square