#include <omp.h> #include <iostream> int main(int argc, char** argv) { { int nThreads = 4; omp_set_num_threads( nThreads ); int x = -1; std::cout << "before parallel " << " x = " << x << " addr = " << &x << std::endl; #pragma omp parallel for lastprivate(x...
十四、private, firstprivate,lastprivate 及 shared指令控制变量共享方式 这些指令用于控制变量在线程组中多个线程之间的共享方式。其中private,firstprivate,lastprivate表示变量的共享方式是私有的,即每个线程都有一份自己的拷贝;而shared表示线程组的线程访问的是同一个变量。 私有变量共享方式有三种指令,它们的区别在于: ...
#pragma omp parallel for private(x) reduction(+:sum) for (i=0; i<num_steps; i++) { x = (i + .5)*step; sum = sum + 4.0/(1.+ x*x); } (您还可以编写sum += 4.0 /(1. + x * x); ) - Hristo Iliev 3 尝试将 sum = sum + 4.0/( 1. + x*x ) 改为sum += ...
void omp_lastprivate() { int n = 8; int i, a = 3; // lastprivate 将for中最后一次循环(i == n-1) a 的值赋给a #pragma omp parallel for private(i) lastprivate(a) for ( i = 0; i<n; i++) { a = i+1; printf("In for: thread %d has a value of a = %d for i =...
print *, "Using", num_threads, "threads for parallel computation." !$omp parallel do private(thread_id, i) do i = 1, n thread_id = omp_get_thread_num() result(i) = array(i) * 2.0 end do !$omp end parallel do ! 验证结果 ...
private(i) shared(n) for(i = 0; i < n; i++) { printf("thread %d execute loop %d\n", omp_get_thread_num(), i); } } void omp_firstprivate() { int n = 8; int i=0, a[n]; for(i = 0; i < n ;i++) { a[i] = i+1; } #pragma omp parallel for private(i) fi...
(omp_get_num_procs());//omp_set_num_threads(1);//int iteration=0;bestPoses.clear();#pragmaomp parallel for private(alpha,alphaBin,alphaScene,sameFeatureIt,index,feature,si,_pointTwoTransformed)//reduction(+:iteration) //nowaitfor(unsignedintsr=0; sr < referencePointsIndices->indices.size...
即负责用给定的操作符将这些拷贝的局部变量的值进行聚合,并设置回共享变量。...I change n to my ID: 4 Data race happened and final n is: 3 */ #pragma omp parallel private(n) 用于控制变量在线程组中多个线程之间的共享方式...; lastprivate:变量在每个线程的共享方式与private一致,但不同的是,变量...
#pragma omp parallel for private(i) schedule(static) shared(x) for(i=0;i<MAX_D;i++) x[i] = x[i]*x[i]; t=omp_get_wtime()-t; printf('Squared in %.3lf secn',t); return 0; } 代码中,首先需要使用omp_set_num_threads设置要使用的线程数量,然后使用omp_get_max_threads获取最大...
$OMP PARALLEL DO PRIVATE(j,filename,varname,buf) j = OMP_GET_THREAD_NUM()$OMP END PARALLEL DO 我正在使用ftn和netcdf4库在CRAY机器中编译代码。a.out: posixio. 浏览3提问于2019-11-18得票数 0 1回答 为什么OpenMP原子和关键不能给出正确的结果? 、 ] atmp=a write(*,'(1X,10I4)') a+b...