3 REAL FUNCTION SEVAL3(N, U, X, Y, B, C, D, deriv, deriv2)
5 REAL U, X(N), Y(N), B(N), C(N), D(N), deriv
42 IF ( u .LT. x(i) )
GO TO 10
43 IF ( u .LE. x(i+1) )
GO TO 30
50 IF ( u .LT. x(k) ) j = k
51 IF ( u .GE. x(k) ) i = k
52 IF ( j .GT. i+1 )
GO TO 20
58 seval3 = y(i) + dx*(b(i) + dx*(c(i) + dx*d(i)))
59 deriv = b(i) + dx*(2.0*c(i) + dx*3.0*d(i))
60 deriv2 = 2.0*c(i) + dx*6.0*d(i)
63 zslop=(y(n)-y(n-1))/(x(n)-x(n-1))
65 zslop=(y(i+1)-y(i))/(x(i+1)-x(i))