Count1存储着call system_clock(count1,count_rate,count_max)时返回的时间戳,Count2存储再次调用该函数时返回的时间戳,其中count1表示当前时间与世界协调时间(格林尼治时间UTC1970/01/01 00:00:00,对应的北京时间为1970/01/01 08:00:00)的时间差值,单位是秒。 Count2的含义为:每经过系统内的一个时钟周期,cou...
call system_clock(count [, count_rate] [, count_max])从系统时钟获取当前时间,count为整型变量,存储当天时间到毫秒。如果要计算长时间运行的程序时间,则需要添加count_max参数来增大统计上限或者改用data_and_time 结语 这只是统计运行时间的一种简单实现方法,但可以满足我的需求,更优的方法还有待摸索! 参考资...
system_clock用于决定处理器时钟周期.count_rate用于决定每秒CPU的时钟计数,PROGRAM test_system_clockINTEGER ::count,count_rate,count_maxCALL SYSTEM_CLOCK(count,count_rate,count_max)WRITE(*,*) count,count_rate,count_maxEND PROGRAM 解析看不懂?免费查看同类题视频解析查看解答...
call system_clock(t1) call system_clock(count=ic, count_rate=crate, count_max=cmax) call system_clock(count=ic2, count_rate=crate2, count_max=cmax2) call system_clock(count=ic4, count_rate=crate4, count_max=cmax4) call system_clock(t2) print *, t1, t2 print *, ic, crate, cm...
=== call system_clock(count=start_count , count_rate=rate) !=== call random_number ( r ) c = 0.4 + 0.02*( 0.5 - r ) do step = 1, steps do concurrent ( integer :: i=1:x, j=1:y ) f(i,j) = 24.0*c(i,j)*( 1.50 - c(i,j) )**2 - & &c...
system_clock用于决定处理器时钟周期.count_rate用于决定每秒CPU的时钟计数,PROGRAM test_system_clockINTEGER ::count,count_rate,count_maxCALL SYSTEM_CLOCK(count,count_rate,count_max)WRITE(*,*) count,count_rate,count_maxEND PROGRAM 解析看不懂?免费查看同类题视频解析查看解答...
system_clock用于决定处理器时钟周期。count_rate用于决定每秒CPU的时钟计数,PROGRAM test_system_clock INTEGER :: count, count_rate, count_max CALL SYSTEM_CLOCK(count, count_rate, count_max)WRITE(*,*) count, count_rate, count_max END PROGRAM 摘自 http://gcc.gnu.org/onlinedocs/...
现在我们再进行一个简单的速度对比看看,首先我们在Euler_Forward这个子程序里添加一个system_clock的计时,然后把它输出出来: subroutine Euler_Forward use com integer t1,t2 CFL = 0.2 dt = CFL*hx t = 0 call system_clock(t1) ! 中间和之前一样,在此略去 call system_clock(t2) if (myid1 == 1) ...
Fortran计时函数库:Fortran中常用的计时函数库包括SYSTEM_CLOCK和CPU_TIME。SYSTEM_CLOCK函数返回一个整数值,表示从某个固定时间点开始的CPU时钟周期数。CPU_TIME函数返回一个实数值,表示程序执行的CPU时间。可以根据具体需求选择适合的函数库。 Fortran计时示例代码: ...
call cpu_time(start) do i = 1, n c(i) = a(i) + b(i) end do call cpu_time(end) print *, 'Manual loop computation time:', end - start contains subroutine cpu_time(time) real, intent(out) :: time call system_clock(count, count_rate) ...