call to system - CPU time

[ndsr]

HI,

I would like to know the CPU time and I should call it in my script

specify the call to the system subroutine to learn CPU time

SUBROUTINE TIMEL(TRES)

************************************************************

* Returns CPU time. *

************************************************************

REAL*8 TRES,TRES0

INTRINSIC SYSTEM_CLOCK

C EXTERNAL CPSEC

SAVE IF,TRES0,IRES0

DATA IF/0/

* THIS IS THE <> CALL TO LEARN CPU TIME

C TRES=MCLOCK()/100.d0

C RETURN

* THIS IS THE <> CALL TO LEARN CPU TIME

C CALL DCLOCK@(TRES)

C IF(IF.EQ.0)TRES0=TRES

C IF=1

C TRES=TRES-TRES0

C RETURN

* THIS IS INTRINSIC PROCEDURE IN FORTRAN<90>

C IF(IF.EQ.0)CALL SYSTEM_CLOCK(IRES0,IRESR,IRESM)

C IF=1

C CALL SYSTEM_CLOCK(IRES,IRESR,IRESM)

C TRES=DBLE(IRES-IRES0)/DBLE(IRESR)

* THIS IS THE MICROSOFT FORTRAN POWER STATION CALL

C IF(IF.EQ.0)TRES0=CPSEC()

C TRES=CPSEC()

C TRES=TRES-TRES0

C IF=1

TRES=0.D0

END

this is the script and where should I specify the call

Pl advice me

[rreis]

The piece of program already tells you how to do it, after each * line there is the code for doing what you want, you just have to uncomment it (remove the initial "C" of each line).

In what architecture will you running this program?

[ndsr]

Dear Reis,

I would like to run this on a 32 bit architecture and my processor speed is 2.93 Ghz. So how should I specify

[TimP]

You might take into account that system_clock() works much better with 64-bit integers. One more reason for explicit declarations.

[ndsr]

HOw can I able to specify 64 bit when my system architecture is 32-bit

[TimP]

You choose the 35 year old non-standard way of specifying 64-bit real, if you choose to be further non-standard you can so the same with integer (integer*8), or you can adopt the way which came in together with system_clock:
integer(selected_int_kind(12)) :: ires0,iresr,iresm,ires

[Steven_L_Intel1]

Intel Fortran for IA-32 supports 64-bit integers.

[ndsr]

Thank you TIM

but can you put that in the code which I've geiven so that would give me clearly

[mecej4 · Accepted solution]

[bash]      SUBROUTINE TIMEL(TRES)
************************************************************
* Returns CPU time.  Fortran 9X version                          *
************************************************************
      REAL*8 TRES,TRES0
      SAVE IF,TRES0,IRES0
      DATA IF/0/
* THIS IS INTRINSIC PROCEDURE IN FORTRAN<90>
     IF(IF.EQ.0)CALL SYSTEM_CLOCK(IRES0,IRESR,IRESM)
     IF=1
     CALL SYSTEM_CLOCK(IRES,IRESR,IRESM)
     TRES=DBLE(IRES-IRES0)/DBLE(IRESR)
      END
[/bash]

[Steven_L_Intel1]

Please note that SYSTEM_CLOCK returns "wall clock" elapsed time, not CPU time. The CPU_TIME intrinsic returns that.

[ndsr]

It has been so long and after my PC crashed out. I reinstated my PC and Now I exactly got what I can do I'll keep posted on the improvement