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```SUBROUTINE DDET5

PURPOSE
TO COMPUTE A VECTOR OF DERIVATIVE VALUES GIVEN A VECTOR OF
FUNCTION VALUES WHOSE ENTRIES CORRESPOND TO EQUIDISTANTLY
SPACED ARGUMENT VALUES.

USAGE
CALL DDET5(H,Y,Z,NDIM,IER)

DESCRIPTION OF PARAMETERS
H	 -  DOUBLE PRECISION CONSTANT DIFFERENCE BETWEEN
SUCCESSIVE ARGUMENT VALUES (H IS POSITIVE IF THE
ARGUMENT VALUES INCREASE AND NEGATIVE OTHERWISE)
Y	 -  GIVEN VECTOR OF DOUBLE PRECISION FUNCTION VALUES
(DIMENSION NDIM)
Z	 -  RESULTING VECTOR OF DOUBLE PRECISION DERIVATIVE
VALUES (DIMENSION NDIM)
NDIM  -  DIMENSION OF VECTORS Y AND Z
IER	 -  RESULTING ERROR PARAMETER
IER = -1  - NDIM IS LESS THAN 5
IER =  0  - NO ERROR
IER =  1  - H = 0

REMARKS
(1)	 IF IER = -1,1, THEN THERE IS NO COMPUTATION.
(2)	 Z CAN HAVE THE SAME STORAGE ALLOCATION AS Y.  IF Y IS
DISTINCT FROM Z, THEN IT IS NOT DESTROYED.

SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
NONE

METHOD
IF X IS THE (SUPPRESSED) VECTOR OF ARGUMENT VALUES, THEN
EXCEPT AT THE POINTS X(1),X(2),X(NDIM-1) AND X(NDIM), Z(I)
IS THE DERIVATIVE AT X(I) OF THE LAGRANGIAN INTERPOLATION
POLYNOMIAL OF DEGREE 4 RELEVANT TO THE 5 SUCCESSIVE POINTS
(X(I+K),Y(I+K)) K = -2,-1,...,2.  (SEE HILDEBRAND, F.B.,
INTRODUCTION TO NUMERICAL ANALYSIS, MC GRAW-HILL, NEW YORK/
TORONTO/LONDON, 1956, PP. 82-84.)

```