C MATHFNC2.F OF N.TAJIMA'S FORTRAN BENCH-MARK TESTS (VER.2)
C MEASURES THE CPU TIME FOR THE EVALUATION OF "EXP", "LOG", AND "ATAN2"
C HISTORY: 98/6/30
      PROGRAM MATHF2
      IMPLICIT REAL*8 (A-H,O-Z)
      A=0.1D0
      B=0.9D0
      N=100000000
      CALL MTHF2B(A,B,N)
      END
C
      SUBROUTINE MTHF2B(A,B,N)
      IMPLICIT REAL*8 (A-H,O-Z)
      D=(B-A)/N
      X0=A-D/2
      S=0
      DO 10 I=1,N
      X=D*I+X0
   10 S=S+ATAN2(EXP(X),LOG(X+1.0D0))
      WRITE(6,900) A,B,N,D*S
  900 FORMAT(' INTEGRAL[',2F4.1,':',I10,' STEPS]'
     & ,'ATAN2(EXP(X),LOG(X+1))DX=',F14.9)
      END