PPT スライド

/* 積分の準備 */

myNinterval = Ninterval / Nproc;

deltax = (upperx - lowerx) / Ninterval;

mylowerx = lowerx + (upperx - lowerx)/Nproc * myID;

/* 積分の実行 */

for(i = 1; i <= myNinterval; i++) {

x = mylowerx + deltax * (i - 0.5);

myintegral += deltax * integrand(x);

}

………………………………………………………………………….

double integrand(double x)

{return 4.0 / (1.0 + x * x);}