bdiff.f 977 B

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  1. *DECK BDIFF
  2. SUBROUTINE BDIFF (L, V)
  3. C***BEGIN PROLOGUE BDIFF
  4. C***SUBSIDIARY
  5. C***PURPOSE Subsidiary to BSKIN
  6. C***LIBRARY SLATEC
  7. C***TYPE SINGLE PRECISION (BDIFF-S, DBDIFF-D)
  8. C***AUTHOR Amos, D. E., (SNLA)
  9. C***DESCRIPTION
  10. C
  11. C BDIFF computes the sum of B(L,K)*V(K)*(-1)**K where B(L,K)
  12. C are the binomial coefficients. Truncated sums are computed by
  13. C setting last part of the V vector to zero. On return, the binomial
  14. C sum is in V(L).
  15. C
  16. C***SEE ALSO BSKIN
  17. C***ROUTINES CALLED (NONE)
  18. C***REVISION HISTORY (YYMMDD)
  19. C 820601 DATE WRITTEN
  20. C 891214 Prologue converted to Version 4.0 format. (BAB)
  21. C 900328 Added TYPE section. (WRB)
  22. C***END PROLOGUE BDIFF
  23. INTEGER I, J, K, L
  24. REAL V
  25. DIMENSION V(*)
  26. C***FIRST EXECUTABLE STATEMENT BDIFF
  27. IF (L.EQ.1) RETURN
  28. DO 20 J=2,L
  29. K = L
  30. DO 10 I=J,L
  31. V(K) = V(K-1) - V(K)
  32. K = K - 1
  33. 10 CONTINUE
  34. 20 CONTINUE
  35. RETURN
  36. END