evnnot Subroutine

subroutine evnnot ( break, coef, l, k, brknew, lnew, coefg )

  !*****************************************************************************80
  !
  !! EVNNOT is a version of NEWNOT returning uniform knots.
  !
  !  Discussion:
  !
  !    EVNNOT returns LNEW+1 knots in BRKNEW which are evenly spaced between 
  !    BREAK(1) and BREAK(L+1).
  !
  !  Modified:
  !
  !    14 February 2007
  !
  !  Author:
  !
  !    Carl DeBoor
  !
  !  Reference:
  !
  !    Carl DeBoor,
  !    A Practical Guide to Splines,
  !    Springer, 2001,
  !    ISBN: 0387953663,
  !    LC: QA1.A647.v27.
  !
  !  Parameters:
  !
  !    Input, real ( kind = 8 ) BREAK(L+1), real ( kind = 8 ) COEF(K,L), 
  !    integer ( kind = 4 ) L, integer K, the piecewise polynomial representation 
  !    of a certain function F of order K.  Specifically,
  !      d**(K-1) F(X) = COEF(K,I) for BREAK(I) <= X < BREAK(I+1).
  !
  !    Input, integer ( kind = 4 ) LNEW, the number of subintervals into which 
  !    the interval (A,B) is to be sectioned by the new breakpoint
  !    sequence BRKNEW.
  !
  !    Output, real ( kind = 8 ) BRKNEW(LNEW+1), the new breakpoints.
  !
  !    Output, real (kind = 8 ) COEFG(2,L), the coefficient part of the 
  !    piecewise polynomial representation BREAK, COEFG, L, 2 for the monotone 
  !    piecewise linear function G with respect to which BRKNEW will
  !    be equidistributed.
  !
  implicit none

  integer ( kind = 4 ) k
  integer ( kind = 4 ) l
  integer ( kind = 4 ) lnew

  real ( kind = 8 ) break(l+1)
  real ( kind = 8 ) brknew(lnew+1)
  real ( kind = 8 ) coef(k,l)
  real ( kind = 8 ) coefg(2,l)
  integer ( kind = 4 ) i

  coefg(2,l) = 0.0D+00

  if ( lnew == 0 ) then

     brknew(1) = 0.5D+00 * ( break(1) + break(l+1) )

  else

     do i = 1, lnew + 1
        brknew(i) = ( real ( lnew - i + 1, kind = 8 ) * break(1) &
             + real (        i - 1, kind = 8 ) * break(l+1) ) &
             / real ( lnew,         kind = 8 )
     end do

  end if

  return
end subroutine evnnot