Add result of test to compare diferent methods

Signed-off-by: Gustavo Toshi Komura <gtk10@c3sl.ufpr.br>
Change definition of PI to const of math.h MI_PI

Signed-off-by: Gustavo Toshi Komura <gtk10@c3sl.ufpr.br>
Put code on standard and uncomment parallel code

Signed-off-by: Gustavo Toshi Komura <gtk10@c3sl.ufpr.br>