Implement sparse * diagonal and diagonal * sparse operations, double-prec only. Date: Sun, 8 Mar 2009 16:28:18 -0400 These preserve sparsity, so eye(5) * sprand (5, 5, .2) is *sparse* and not dense. This may affect people who use multiplication by eye() rather than full(). The liboctave routines do *not* check if arguments are scalars in disguise. There is a type problem with checking at that level. I suspect we want diag * "sparse scalar" to stay diagonal, but we have to return a sparse matrix at the liboctave. Rather than worrying about that in liboctave, we cope with it when binding to Octave and return the correct higher-level type. The implementation is in Sparse-diag-op-defs.h rather than Sparse-op-defs.h to limit recompilation. And the implementations are templates rather than macros to produce better compiler errors and debugging information.

      SUBROUTINE ZMLT(AR, AI, BR, BI, CR, CI)
C***BEGIN PROLOGUE  ZMLT
C***REFER TO  ZBESH,ZBESI,ZBESJ,ZBESK,ZBESY,ZAIRY,ZBIRY
C
C     DOUBLE PRECISION COMPLEX MULTIPLY, C=A*B.
C
C***ROUTINES CALLED  (NONE)
C***END PROLOGUE  ZMLT
      DOUBLE PRECISION AR, AI, BR, BI, CR, CI, CA, CB
      CA = AR*BR - AI*BI
      CB = AR*BI + AI*BR
      CR = CA
      CI = CB
      RETURN
      END