PROGRAM series8 ! ! Author: Br. David Carlson ! ! Date: January 2, 2000 ! ! Revised: May 2, 2004 ! ! This program prints out partial sums for the Fourier series in problem 5 ! page 19 of Bressoud's text, A Radical Approach to Real Analysis. IMPLICIT NONE REAL::term, sum, f, x, piover2 INTEGER::n, sign, count, k WRITE (*, 20) 20 FORMAT (1X, 'Program to investigate a Fourier series') WRITE (*, *) 'Enter the number of terms N to use: ' READ (*, *) n WRITE (*, *) 'Enter the value of X at which to evaluate the partial sums: ' READ (*, *) x sum = 0.0 sign = 1 count = 0 piover2 = ASIN(1.0) WRITE (*, 50) 50 FORMAT (' ', T5, 'count', T15, 'term', T35, 'partial sum', T55, 'f') DO k = 1, 2 * n - 1, 2 count = count + 1 term = sign * COS(k * piover2 * x) / k sum = sum + term f = 2.0 * sum / piover2 WRITE (*, 100) count, term, sum, f sign = -sign END DO 100 FORMAT (' ', T5, I4, T15, E16.8, T35, E16.8, T55, E16.8) END PROGRAM