*DECK POISN2 SUBROUTINE POISN2 (M, N, ISTAG, MIXBND, A, BB, C, Q, IDIMQ, B, B2, + B3, W, W2, W3, D, TCOS, P) C***BEGIN PROLOGUE POISN2 C***SUBSIDIARY C***PURPOSE Subsidiary to GENBUN C***LIBRARY SLATEC C***TYPE SINGLE PRECISION (POISN2-S, CMPOSN-C) C***AUTHOR (UNKNOWN) C***DESCRIPTION C C Subroutine to solve Poisson's equation with Neumann boundary C conditions. C C ISTAG = 1 if the last diagonal block is A. C ISTAG = 2 if the last diagonal block is A-I. C MIXBND = 1 if have Neumann boundary conditions at both boundaries. C MIXBND = 2 if have Neumann boundary conditions at bottom and C Dirichlet condition at top. (for this case, must have ISTAG = 1.) C C***SEE ALSO GENBUN C***ROUTINES CALLED COSGEN, S1MERG, TRI3, TRIX C***REVISION HISTORY (YYMMDD) C 801001 DATE WRITTEN C 890531 Changed all specific intrinsics to generic. (WRB) C 891214 Prologue converted to Version 4.0 format. (BAB) C 900402 Added TYPE section. (WRB) C 920130 Modified to use merge routine S1MERG rather than deleted C routine MERGE. (WRB) C***END PROLOGUE POISN2