dsecndtst (l) - Linux Manuals

NAME

SYNOPSIS

PROGRAM TEST5

    

INTEGER NMAX, ITS

    

PARAMETER ( NMAX = 100, ITS = 5000 )

    

INTEGER I, J

    

DOUBLE PRECISION ALPHA, AVG, T1, T2, TNOSEC

    

DOUBLE PRECISION X( NMAX ), Y( NMAX )

    

DOUBLE PRECISION DSECND

    

EXTERNAL DSECND

    

INTRINSIC DBLE

    

DO 10 I = 1, NMAX

    

X( I ) = DBLE( 1 ) / DBLE( I )

    

Y( I ) = DBLE( NMAX-I ) / DBLE( NMAX )

    

10 CONTINUE

    

ALPHA = 0.315D0

    

T1 = DSECND( )

    

DO 30 J = 1, ITS

    

DO 20 I = 1, NMAX

    

Y( I ) = Y( I ) + ALPHA*X( I )

    

20 CONTINUE

    

ALPHA = -ALPHA

    

30 CONTINUE

    

T2 = DSECND( )

    

WRITE( 6, 9999 )T2 - T1

    

IF( T2-T1.GT.0.0D0 ) THEN

    

WRITE( 6, 9998 )1.0D0 / ( T2-T1 )

    

ELSE

    

WRITE( 6, 9994 )

    

END IF

    

TNOSEC = T2 - T1

    

T1 = DSECND( )

    

DO 50 J = 1, ITS

    

DO 40 I = 1, NMAX

    

Y( I ) = Y( I ) + ALPHA*X( I )

    

40 CONTINUE

    

ALPHA = -ALPHA

    

T2 = DSECND( )

    

50 CONTINUE

    

WRITE( 6, 9997 )T2 - T1

    

AVG = ( ( T2-T1 )-TNOSEC )*1000.D0 / DBLE( ITS )

    

WRITE( 6, 9996 )AVG

    

IF( TNOSEC.GT.0.0D0 ) WRITE( 6, 9995 )1000.D0*AVG / TNOSEC

    

9999 FORMAT( aq Time for 1,000,000 DAXPY ops = aq, G10.3, aq secondsaq )

    

9998 FORMAT( aq DAXPY performance rate = aq, G10.3, aq mflops aq )

    

9997 FORMAT( aq Including DSECND, time = aq, G10.3, aq secondsaq )

    

9996 FORMAT( aq Average time for DSECND = aq, G10.3, aq millisecondsaq )

    

9995 FORMAT( aq Equivalent floating point ops = aq, G10.3, aq opsaq )

    

9994 FORMAT( aq *** Error: Time for operations was zeroaq )

    

CALL MYSUB(NMAX,X,Y)

    

END

    

SUBROUTINE MYSUB(N,X,Y)

    

INTEGER N

    

DOUBLE PRECISION X(N), Y(N)

    

RETURN

    

END

PURPOSE