TIMUR_EKZ

PROGRAM TIMUR_EKZ
REAL INTEGRAL1, N1, PI, A, B
PARAMETER(PI = 3.141)
1 FORMAT (A46)
2 FORMAT ('|', F8.5, '  |', I12, '          |', F9.6, ' |')
E1 = 0.0001
OPEN(1, FILE='INPUT.TXT')
READ (1, *) A, B
CLOSE(1)
CALL INTEGRAL_FIND(A, B, INTEGRAL1, N1)
PRINT 1, '----------------------------------------------'
PRINT 1, '| ACCURACY | NUMBER OF ITERATIONS | INTEGRAL |'
PRINT 1, '+----------+----------------------+----------+'
PRINT 2, E1, INT(N1), INTEGRAL1
PRINT 1, '----------------------------------------------'
END

SUBROUTINE INTEGRAL_FIND(A, B, INTEGRAL, N)
REAL INTEGRAL, OLD_INTEGRAL, S, H, N, A, B
INTEGER I
INTEGRAL = 0
OLD_INTEGRAL = 1
N = 0
DO K = 1, 25
N = N + 20
OLD_INTEGRAL = INTEGRAL
INTEGRAL = 0
H = (B - A) / N
S = 0
DO I=1, INT(N-1)
S = S + F(A + H*I)
END DO
INTEGRAL = H * ((F(REAL(A))+F(REAL(B)))/2+S)
END DO
END SUBROUTINE

REAL FUNCTION F(X)
F = 1 / (5 - 3 * COS(X))
RETURN
END