SLATEC Routines --- SPELI4 ---


*DECK SPELI4
      SUBROUTINE SPELI4 (IORDER, A, B, M, MBDCND, BDA, ALPHA, BDB, BETA,
     +   C, D, N, NBDCND, BDC, BDD, COFX, AN, BN, CN, DN, UN, ZN, AM,
     +   BM, CM, DM, UM, ZM, GRHS, USOL, IDMN, W, PERTRB, IERROR)
C***BEGIN PROLOGUE  SPELI4
C***SUBSIDIARY
C***PURPOSE  Subsidiary to SEPX4
C***LIBRARY   SLATEC
C***TYPE      SINGLE PRECISION (SPELI4-S)
C***AUTHOR  (UNKNOWN)
C***DESCRIPTION
C
C     SPELI4 sets up vectors and arrays for input to BLKTRI
C     and computes a second order solution in USOL.  A return jump to
C     SEPX4 occurs if IORDER=2.  If IORDER=4 a fourth order
C     solution is generated in USOL.
C
C***SEE ALSO  SEPX4
C***ROUTINES CALLED  CHKSN4, DEFE4, GENBUN, MINSO4, ORTHO4, TRIS4
C***COMMON BLOCKS    SPL4
C***REVISION HISTORY  (YYMMDD)
C   801001  DATE WRITTEN
C   890531  Changed all specific intrinsics to generic.  (WRB)
C   891009  Removed unreferenced variable.  (WRB)
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C   900402  Added TYPE section.  (WRB)
C***END PROLOGUE  SPELI4