SUBROUTINE DET5 PURPOSE TO COMPUTE A VECTOR OF DERIVATIVE VALUES GIVEN A VECTOR OF FUNCTION VALUES WHOSE ENTRIES CORRESPOND TO EQUIDISTANTLY SPACED ARGUMENT VALUES. USAGE CALL DET5(H,Y,Z,NDIM,IER) DESCRIPTION OF PARAMETERS H - CONSTANT DIFFERENCE BETWEEN SUCCESSIVE ARGUMENT VALUES (H IS POSITIVE IF THE ARGUMENT VALUES INCREASE AND NEGATIVE OTHERWISE) Y - GIVEN VECTOR OF FUNCTION VALUES (DIMENSION NDIM) Z - RESULTING VECTOR OF 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.)