Question

我一直在查看代码

npoints = 10000
circle_count = 0

p = number of tasks
num = npoints/p

find out if I am MASTER or WORKER 

do j = 1,num 
  generate 2 random numbers between 0 and 1
  xcoordinate = random1
  ycoordinate = random2
  if (xcoordinate, ycoordinate) inside circle
  then circle_count = circle_count + 1
end do

if I am MASTER

  receive from WORKERS their circle_counts
  compute PI (use MASTER and WORKER calculations)

else if I am WORKER

  send to MASTER circle_count

endif

任何人都可以告诉这个算法使用什么级别的并行性？我问的是平行度的水平 1）工作或计划水平 2）任务或程序级别 3）内部指令级别 4）内部指令级

Answer 1

这是monte carlo方法，运行得越多，你将会追溯到更准确的结果。

  do j = 1,num 
  generate 2 random numbers between 0 and 1
  xcoordinate = random1
  ycoordinate = random2
  if (xcoordinate, ycoordinate) inside circle
  then circle_count = circle_count + 1
  end do

上面的代码是蒙特卡罗步骤，它可以在独立运行的num个线程中并行化（只要在线程之间共享circle_count变量）。在创建所有点之后，您可以返回单线程来计算pi值。

pi计算中的并行度

1 个答案: