5 * Revision 1.1.1.1 1996/04/01 15:02:25 mclareni
10 SUBROUTINE DSPIN2(KX,KY,NX,NY,XI,YI,ZI,NDIMZ,KNOT,TX,TY,C,NDIMC,
13 #include "gen/imp64.inc"
14 DIMENSION XI(*),YI(*),ZI(NDIMZ,*),TX(*),TY(*)
15 DIMENSION W(*),IW(*),C(NDIMC,*)
18 PARAMETER (NAME = 'DSPIN2')
21 ************************************************************************
22 * NORBAS, VERSION: 10.02.1993
23 ************************************************************************
25 * DSPIN2 COMPUTES THE COEFFICIENTS
26 * C(I,J) (I=1,...,NX , J=1,...,NY)
27 * OF A TWO-DIMENSIONAL POLYNOMIAL INTERPOLATION SPLINE Z = S(X,Y) IN
28 * REPRESENTATION OF NORMALIZED TWO-DIMENSIONAL B-SPLINES B(I,J)(X,Y)
30 * S(X,Y) = SUMME(I=1,...,NX)
31 * SUMME(J=1,...,NY) C(I,J) * B(I,J)(X,Y)
33 * TO A USER SUPPLIED DATA SET
35 * (XI(I),YI(J),ZI(I,J)) (I=1,...,NX , J=1,...,NY)
37 * OF A FUNCTION Z = F(X,Y) , I.E.
39 * S(XI(I),YI(J)) = Z(I,J) (I=1,...,NX , J=1,...,NY) .
41 * THE TWO-DIMENSIONAL B-SPLINES B(I,J)(X,Y) ARE THE PRODUCT OF TWO
42 * ONE-DIMENSIONAL B-SPLINES BX , BY
43 * B(I,J)(X,Y) = BX(I,KX)(X) * BY(J,KY)(Y)
44 * OF DEGREE KX AND KY ( 0 <= KX , KY <= 25 ) WITH INDICES I , J
45 * ( 1 <= I <= NX , 1 <= J <= NY ) OVER TWO SETS OF SPLINE-KNOTS
46 * TX(1),TX(2),...,TX(MX) ( MX = NX+KX+1 )
47 * TY(1),TY(2),...,TY(MY) ( MY = NY+KY+1 ) ,
49 * FOR FURTHER DETAILS TO THE ONE- AND TWO-DIMENSIONAL NORMALIZED
50 * B-SPLINES SEE THE COMMENTS TO DSPNB1 AND DSPNB2.
54 * NX (INTEGER) NUMBER OF INTERPOLATION POINTS IN X-DIRECTION :
55 * XI(I) , I=1,...,NX .
56 * NY (INTEGER) NUMBER OF INTERPOLATION POINTS IN Y-DIRECTION :
57 * YI(J) , J=1,...,NY .
58 * KX (INTEGER) DEGREE OF ONE-DIMENSIONAL B-SPLINES IN X-DIRECTION
59 * OVER THE SET OF KNOTS TX,
60 * WITH KX <= NX-1 AND 0 <= KX <= 25 .
61 * KY (INTEGER) DEGREE OF ONE-DIMENSIONAL B-SPLINES IN Y-DIRECTION
62 * OVER THE SET OF KNOTS TY,
63 * WITH KY <= NY-1 AND 0 <= KY <= 25 .
64 * NDIMC (INTEGER) DECLARED FIRST DIMENSION OF ARRAY C IN THE
65 * CALLING PROGRAM, WITH NDIMC >= NX .
66 * NDIMZ (INTEGER) DECLARED FIRST DIMENSION OF ARRAY ZI IN THE
67 * CALLING PROGRAM, WITH NDIMZ >= NX .
68 * XI (DOUBLE PRECISION) ARRAY OF AT LEAST ORDER NX .
69 * XI MUST CONTAIN THE INTERPOLATION POINTS IN X-DIRECTION IN
70 * ASCENDING ORDER, ON ENTRY.
71 * YI (DOUBLE PRECISION) ARRAY OF AT LEAST ORDER NY .
72 * YI MUST CONTAIN THE INTERPOLATION POINTS IN Y-DIRECTION IN
73 * ASCENDING ORDER, ON ENTRY.
74 * ZI (DOUBLE PRECISION) ARRAY OF ORDER (NDIMZ , >= NY) .
75 * ON ENTRY ZI MUST CONTAIN THE GIVEN FUNCTION VALUES
76 * Z(I,J) AT THE INTERPOLATION POINTS (X(I),Y(J))
77 * ( I=1,...,NX , J=1,...,NY ).
78 * KNOT (INTEGER) PARAMETER FOR STEERING THE CHOICE OF KNOTS.
80 * = 1 : KNOTS ARE COMPUTED BY DSPIN2 IN THE FOLLOWING WAY:
81 * TX(J) = XI(1) , J = 1,...,KX+1
82 * TX(J) = XI(1)+(J-KX-1)*(XI(NX)-XI(1)) ,
84 * TX(N+J) = XI(NX) , J = 1,...,KX+1
85 * = 2 : KNOTS ARE COMPUTED BY DSPIN2 IN THE FOLLOWING WAY:
86 * TX(J) = XI(1) , J = 1,...,KX+1
87 * TX(J) = (XI(J-KX-1)+XI(J))/2 , J = KX+2,...,NX
88 * TX(N+J) = XI(NX) , J = 1,...,KX+1
89 * OTHERWISE KNOTS ARE USER SUPPLIED. RECOMMENDED CHOICE :
90 * T(1) <= ... <= T(K+1) <= XI(1)
91 * XI(1) < T(K+2) < ... < T(N) < XI(N)
92 * XI(N) <= T(N+1) <= ... <= T(N+K+1)
93 * OTHERWISE KNOTS ARE USER SUPPLIED. RECOMMENDED CHOICE :
94 * TX(1) <= ... <= TX(KX+1) <= XI(1)
95 * XI(1) < TX(KX+2) < ... < TX(NX) < XI(NX)
96 * XI(NX) <= TX(NX+1) <= ... <= TX(NX+KX+1)
97 * IN ALL CASES THE SAME CHOICE IS USED FOR KNOTS TY IN
99 * TX (DOUBLE PRECISION) ARRAY OF AT LEAST ORDER MX.
100 * IF THE INPUT VALUE OF THE PARAMETER KNOT IS 1 OR 2 THE
101 * KNOTS ARE COMPUTED BY DSPIN2 AND THEY ARE GIVEN IN THE
103 * IN THE OTHER CASES THE ARRAY TX MUST CONTAIN THE USER
104 * SUPPLIED KNOTS IN X-DIRECTION, ON ENTRY.
105 * TY (DOUBLE PRECISION) ARRAY OF AT LEAST ORDER MY.
106 * IF THE INPUT VALUE OF THE PARAMETER KNOT IS 1 OR 2 THE
107 * KNOTS ARE COMPUTED BY DSPIN2 AND THEY ARE GIVEN IN THE
109 * IN THE OTHER CASES THE ARRAY TY MUST CONTAIN THE USER
110 * SUPPLIED KNOTS IN Y-DIRECTION, ON ENTRY.
111 * W (DOUBLE PRECISION) WORKING ARRAY OF AT LEAST ORDER (L+1)*NINT,
112 * WITH NINT=NX*NY , K=KX*NY , L=3*K+1 .
113 * IW (INTEGER) WORKING ARRAY OF AT LEAST ORDER NX*NY.
114 * C (DOUBLE PRECISION) ARRAY OF ORDER (NDIMC, >= NY).
115 * ON EXIT C(I,J) CONTAINS THE (I,J)-TH COEFFICIENT OF THE
116 * TWO-DIMENSIONAL B-SPLINE REPRESENTATION OF S(X,Y) .
117 * NERR (INTEGER) ERROR INDICATOR. ON EXIT:
118 * = 0: NO ERROR DETECTED
119 * = 1: AT LEAST ONE OF THE CONSTANTS KX , KY , NX , NY
121 * = 2: THE LAPACK ROUTINES DGBTRF , DGBTRS COULD NOT SOLVE
122 * THE LINEAR SYSTEM OF EQUATIONS WITH BAND-MATRIX FOR
123 * COMPUTING C(1,1),...,C(NX,NY) . IT INDICATES THAT
124 * A SOLUTION OF THE INTERPOLATION PROBLEM DOES NOT EXIST.
125 * (ESPECIALLY, THE EXISTENCE OF A SOLUTION DEPENDS ON THE
130 * IF ONE OF THE FOLLOWING RELATION IS SATISFIED BY THE CHOSEN INPUT-
131 * PARAMETERS THE PROGRAM RETURNS, AND AN ERROR MESSAGE IS PRINTED:
132 * KX < 0 OR KX > 25 OR
133 * KY < 0 OR KY > 25 OR
134 * NX < KX+1 OR NY < KY+1 .
136 ************************************************************************
139 PARAMETER (Z1 = 1 , Z2 = 2 , HALF = Z1/Z2)
142 IF(KX .LT. 0 .OR. KX .GT. 25) THEN
143 WRITE(ERRTXT,101) 'KX',KX
144 CALL MTLPRT(NAME,'E210.1',ERRTXT)
145 ELSEIF(KY .LT. 0 .OR. KY .GT. 25) THEN
146 WRITE(ERRTXT,101) 'KY',KY
147 CALL MTLPRT(NAME,'E210.1',ERRTXT)
148 ELSEIF(NX .LT. KX+1) THEN
149 WRITE(ERRTXT,101) 'NX',NX
150 CALL MTLPRT(NAME,'E210.4',ERRTXT)
151 ELSEIF(NY .LT. KY+1) THEN
152 WRITE(ERRTXT,101) 'NY',NY
153 CALL MTLPRT(NAME,'E210.4',ERRTXT)
162 * COMPUTE KNOTS FROM INTERPOLATION POINTS ( IF KNOT=1 OR 2 )
164 IF (KNOT .EQ. 1) THEN
165 CALL DSPKN2(KX,KY,MX,MY,XI(1),XI(NX),YI(1),YI(NY),TX,TY,NERR)
166 ELSEIF (KNOT .EQ. 2) THEN
171 20 TX(I)=HALF*(XI(I-KX-1)+XI(I))
176 40 TY(J)=HALF*(YI(J-KY-1)+YI(J))
179 * COMPUTE BAND-MATRIX W
181 * NUMBER OF SUB-, SUPER-DIAGONALS: KL=KU=(KX-1)*NY+KY-1<=KX*NY
192 IF (K+1 .LE. IZ .AND. IZ .LE. 3*K+1)
193 + W((JZ-1)*L+IZ)=DSPNB2(KX,KY,MX,MY,I,J,0,0,X,Y,TX,TY,NERR)
196 * SOLVE SYSTEM OF EQUATIONS FOR COMPUTING C
201 CALL DGBTRF(NINT,NINT,K,K,W,L,IW,INFO)
202 IF(INFO .NE. 0) RETURN
206 120 W(LW+(I-1)*NY+J)=ZI(I,J)
207 CALL DGBTRS('N',NINT,K,K,1,W,L,IW,W(LW+1),NINT,INFO)
208 IF(INFO .NE. 0) RETURN
211 130 C(I,J)=W(LW+(I-1)*NY+J)
217 101 FORMAT(1X,A5,' =',I6,' NOT IN RANGE')