view libinterp/corefcn/sparse.cc @ 17787:175b392e91fe

Use GNU style coding conventions for code in libinterp/ * libinterp/corefcn/Cell.h, libinterp/corefcn/__contourc__.cc, libinterp/corefcn/__dispatch__.cc, libinterp/corefcn/__lin_interpn__.cc, libinterp/corefcn/__pchip_deriv__.cc, libinterp/corefcn/__qp__.cc, libinterp/corefcn/balance.cc, libinterp/corefcn/besselj.cc, libinterp/corefcn/betainc.cc, libinterp/corefcn/bitfcns.cc, libinterp/corefcn/bsxfun.cc, libinterp/corefcn/c-file-ptr-stream.cc, libinterp/corefcn/c-file-ptr-stream.h, libinterp/corefcn/cellfun.cc, libinterp/corefcn/colloc.cc, libinterp/corefcn/comment-list.h, libinterp/corefcn/conv2.cc, libinterp/corefcn/daspk.cc, libinterp/corefcn/dasrt.cc, libinterp/corefcn/dassl.cc, libinterp/corefcn/data.cc, libinterp/corefcn/debug.cc, libinterp/corefcn/defaults.cc, libinterp/corefcn/defaults.in.h, libinterp/corefcn/defun-int.h, libinterp/corefcn/defun.cc, libinterp/corefcn/det.cc, libinterp/corefcn/dirfns.cc, libinterp/corefcn/display.cc, libinterp/corefcn/dlmread.cc, libinterp/corefcn/dot.cc, libinterp/corefcn/dynamic-ld.cc, libinterp/corefcn/dynamic-ld.h, libinterp/corefcn/eig.cc, libinterp/corefcn/ellipj.cc, libinterp/corefcn/error.cc, libinterp/corefcn/error.h, libinterp/corefcn/event-queue.h, libinterp/corefcn/fft.cc, libinterp/corefcn/fft2.cc, libinterp/corefcn/fftn.cc, libinterp/corefcn/file-io.cc, libinterp/corefcn/filter.cc, libinterp/corefcn/find.cc, libinterp/corefcn/gammainc.cc, libinterp/corefcn/gcd.cc, libinterp/corefcn/getgrent.cc, libinterp/corefcn/getpwent.cc, libinterp/corefcn/getrusage.cc, libinterp/corefcn/givens.cc, libinterp/corefcn/gl-render.cc, libinterp/corefcn/gl2ps-renderer.cc, libinterp/corefcn/gl2ps-renderer.h, libinterp/corefcn/graphics.cc, libinterp/corefcn/graphics.in.h, libinterp/corefcn/gripes.cc, libinterp/corefcn/gripes.h, libinterp/corefcn/help.cc, libinterp/corefcn/hess.cc, libinterp/corefcn/hex2num.cc, libinterp/corefcn/input.cc, libinterp/corefcn/input.h, libinterp/corefcn/inv.cc, libinterp/corefcn/jit-ir.h, libinterp/corefcn/jit-typeinfo.cc, libinterp/corefcn/jit-typeinfo.h, libinterp/corefcn/jit-util.h, libinterp/corefcn/kron.cc, libinterp/corefcn/load-path.cc, libinterp/corefcn/load-path.h, libinterp/corefcn/load-save.cc, libinterp/corefcn/load-save.h, libinterp/corefcn/lookup.cc, libinterp/corefcn/ls-ascii-helper.cc, libinterp/corefcn/ls-hdf5.cc, libinterp/corefcn/ls-hdf5.h, libinterp/corefcn/ls-mat-ascii.cc, libinterp/corefcn/ls-mat-ascii.h, libinterp/corefcn/ls-mat4.cc, libinterp/corefcn/ls-mat5.cc, libinterp/corefcn/ls-mat5.h, libinterp/corefcn/ls-oct-ascii.cc, libinterp/corefcn/lsode.cc, libinterp/corefcn/lu.cc, libinterp/corefcn/luinc.cc, libinterp/corefcn/mappers.cc, libinterp/corefcn/matrix_type.cc, libinterp/corefcn/max.cc, libinterp/corefcn/md5sum.cc, libinterp/corefcn/mex.cc, libinterp/corefcn/mexproto.h, libinterp/corefcn/mgorth.cc, libinterp/corefcn/mxarray.in.h, libinterp/corefcn/nproc.cc, libinterp/corefcn/oct-hist.cc, libinterp/corefcn/oct-lvalue.h, libinterp/corefcn/oct-map.cc, libinterp/corefcn/oct-map.h, libinterp/corefcn/oct-obj.h, libinterp/corefcn/oct-prcstrm.h, libinterp/corefcn/oct-stdstrm.h, libinterp/corefcn/oct-stream.cc, libinterp/corefcn/oct-stream.h, libinterp/corefcn/octave-link.cc, libinterp/corefcn/octave-link.h, libinterp/corefcn/pager.cc, libinterp/corefcn/pinv.cc, libinterp/corefcn/pr-output.cc, libinterp/corefcn/procstream.h, libinterp/corefcn/profiler.cc, libinterp/corefcn/pt-jit.cc, libinterp/corefcn/pt-jit.h, libinterp/corefcn/quad.cc, libinterp/corefcn/quadcc.cc, libinterp/corefcn/qz.cc, libinterp/corefcn/rand.cc, libinterp/corefcn/rcond.cc, libinterp/corefcn/regexp.cc, libinterp/corefcn/schur.cc, libinterp/corefcn/sighandlers.cc, libinterp/corefcn/sighandlers.h, libinterp/corefcn/sparse-xdiv.cc, libinterp/corefcn/sparse-xdiv.h, libinterp/corefcn/sparse-xpow.cc, libinterp/corefcn/sparse.cc, libinterp/corefcn/spparms.cc, libinterp/corefcn/sqrtm.cc, libinterp/corefcn/str2double.cc, libinterp/corefcn/strfind.cc, libinterp/corefcn/strfns.cc, libinterp/corefcn/sub2ind.cc, libinterp/corefcn/svd.cc, libinterp/corefcn/syl.cc, libinterp/corefcn/symtab.cc, libinterp/corefcn/symtab.h, libinterp/corefcn/syscalls.cc, libinterp/corefcn/sysdep.cc, libinterp/corefcn/sysdep.h, libinterp/corefcn/time.cc, libinterp/corefcn/toplev.cc, libinterp/corefcn/toplev.h, libinterp/corefcn/tril.cc, libinterp/corefcn/txt-eng-ft.cc, libinterp/corefcn/txt-eng-ft.h, libinterp/corefcn/txt-eng.h, libinterp/corefcn/typecast.cc, libinterp/corefcn/urlwrite.cc, libinterp/corefcn/utils.cc, libinterp/corefcn/variables.cc, libinterp/corefcn/variables.h, libinterp/corefcn/xdiv.cc, libinterp/corefcn/xdiv.h, libinterp/corefcn/xnorm.h, libinterp/corefcn/xpow.cc, libinterp/corefcn/xpow.h, libinterp/corefcn/zfstream.cc, libinterp/corefcn/zfstream.h, libinterp/dldfcn/__delaunayn__.cc, libinterp/dldfcn/__dsearchn__.cc, libinterp/dldfcn/__eigs__.cc, libinterp/dldfcn/__fltk_uigetfile__.cc, libinterp/dldfcn/__glpk__.cc, libinterp/dldfcn/__init_fltk__.cc, libinterp/dldfcn/__init_gnuplot__.cc, libinterp/dldfcn/__magick_read__.cc, libinterp/dldfcn/__voronoi__.cc, libinterp/dldfcn/amd.cc, libinterp/dldfcn/ccolamd.cc, libinterp/dldfcn/chol.cc, libinterp/dldfcn/colamd.cc, libinterp/dldfcn/convhulln.cc, libinterp/dldfcn/dmperm.cc, libinterp/dldfcn/fftw.cc, libinterp/dldfcn/qr.cc, libinterp/dldfcn/symbfact.cc, libinterp/dldfcn/symrcm.cc, libinterp/dldfcn/tsearch.cc, libinterp/octave-value/ov-base-diag.cc, libinterp/octave-value/ov-base-diag.h, libinterp/octave-value/ov-base-int.cc, libinterp/octave-value/ov-base-int.h, libinterp/octave-value/ov-base-mat.h, libinterp/octave-value/ov-base-scalar.cc, libinterp/octave-value/ov-base-scalar.h, libinterp/octave-value/ov-base-sparse.cc, libinterp/octave-value/ov-base-sparse.h, libinterp/octave-value/ov-base.cc, libinterp/octave-value/ov-base.h, libinterp/octave-value/ov-bool-mat.cc, libinterp/octave-value/ov-bool-mat.h, libinterp/octave-value/ov-bool-sparse.cc, libinterp/octave-value/ov-bool-sparse.h, libinterp/octave-value/ov-bool.cc, libinterp/octave-value/ov-bool.h, libinterp/octave-value/ov-builtin.cc, libinterp/octave-value/ov-builtin.h, libinterp/octave-value/ov-cell.cc, libinterp/octave-value/ov-cell.h, libinterp/octave-value/ov-ch-mat.cc, libinterp/octave-value/ov-ch-mat.h, libinterp/octave-value/ov-class.cc, libinterp/octave-value/ov-class.h, libinterp/octave-value/ov-colon.h, libinterp/octave-value/ov-complex.cc, libinterp/octave-value/ov-complex.h, libinterp/octave-value/ov-cx-diag.cc, libinterp/octave-value/ov-cx-diag.h, libinterp/octave-value/ov-cx-mat.cc, libinterp/octave-value/ov-cx-mat.h, libinterp/octave-value/ov-cx-sparse.cc, libinterp/octave-value/ov-cx-sparse.h, libinterp/octave-value/ov-dld-fcn.h, libinterp/octave-value/ov-fcn-handle.cc, libinterp/octave-value/ov-fcn-handle.h, libinterp/octave-value/ov-fcn-inline.cc, libinterp/octave-value/ov-fcn-inline.h, libinterp/octave-value/ov-fcn.h, libinterp/octave-value/ov-float.cc, libinterp/octave-value/ov-float.h, libinterp/octave-value/ov-flt-complex.cc, libinterp/octave-value/ov-flt-complex.h, libinterp/octave-value/ov-flt-cx-diag.cc, libinterp/octave-value/ov-flt-cx-diag.h, libinterp/octave-value/ov-flt-cx-mat.cc, libinterp/octave-value/ov-flt-cx-mat.h, libinterp/octave-value/ov-flt-re-diag.cc, libinterp/octave-value/ov-flt-re-diag.h, libinterp/octave-value/ov-flt-re-mat.cc, libinterp/octave-value/ov-flt-re-mat.h, libinterp/octave-value/ov-int16.cc, libinterp/octave-value/ov-int32.cc, libinterp/octave-value/ov-int64.cc, libinterp/octave-value/ov-int8.cc, libinterp/octave-value/ov-intx.h, libinterp/octave-value/ov-java.cc, libinterp/octave-value/ov-lazy-idx.h, libinterp/octave-value/ov-mex-fcn.cc, libinterp/octave-value/ov-mex-fcn.h, libinterp/octave-value/ov-null-mat.cc, libinterp/octave-value/ov-null-mat.h, libinterp/octave-value/ov-oncleanup.cc, libinterp/octave-value/ov-perm.cc, libinterp/octave-value/ov-perm.h, libinterp/octave-value/ov-range.cc, libinterp/octave-value/ov-range.h, libinterp/octave-value/ov-re-diag.cc, libinterp/octave-value/ov-re-diag.h, libinterp/octave-value/ov-re-mat.cc, libinterp/octave-value/ov-re-mat.h, libinterp/octave-value/ov-re-sparse.cc, libinterp/octave-value/ov-re-sparse.h, libinterp/octave-value/ov-scalar.cc, libinterp/octave-value/ov-scalar.h, libinterp/octave-value/ov-str-mat.cc, libinterp/octave-value/ov-str-mat.h, libinterp/octave-value/ov-struct.cc, libinterp/octave-value/ov-struct.h, libinterp/octave-value/ov-type-conv.h, libinterp/octave-value/ov-typeinfo.cc, libinterp/octave-value/ov-typeinfo.h, libinterp/octave-value/ov-uint16.cc, libinterp/octave-value/ov-uint32.cc, libinterp/octave-value/ov-uint64.cc, libinterp/octave-value/ov-uint8.cc, libinterp/octave-value/ov-usr-fcn.cc, libinterp/octave-value/ov-usr-fcn.h, libinterp/octave-value/ov.cc, libinterp/octave-value/ov.h, libinterp/octave.cc, libinterp/operators/op-b-bm.cc, libinterp/operators/op-b-sbm.cc, libinterp/operators/op-bm-b.cc, libinterp/operators/op-bm-bm.cc, libinterp/operators/op-cdm-cdm.cc, libinterp/operators/op-chm.cc, libinterp/operators/op-class.cc, libinterp/operators/op-cm-cm.cc, libinterp/operators/op-cm-cs.cc, libinterp/operators/op-cm-s.cc, libinterp/operators/op-cm-scm.cc, libinterp/operators/op-cm-sm.cc, libinterp/operators/op-cs-cm.cc, libinterp/operators/op-cs-cs.cc, libinterp/operators/op-cs-scm.cc, libinterp/operators/op-cs-sm.cc, libinterp/operators/op-dm-dm.cc, libinterp/operators/op-dm-scm.cc, libinterp/operators/op-double-conv.cc, libinterp/operators/op-fcdm-fcdm.cc, libinterp/operators/op-fcm-fcm.cc, libinterp/operators/op-fcm-fcs.cc, libinterp/operators/op-fcm-fm.cc, libinterp/operators/op-fcm-fs.cc, libinterp/operators/op-fcs-fcm.cc, libinterp/operators/op-fcs-fcs.cc, libinterp/operators/op-fcs-fm.cc, libinterp/operators/op-fcs-fs.cc, libinterp/operators/op-fdm-fdm.cc, libinterp/operators/op-float-conv.cc, libinterp/operators/op-fm-fcm.cc, libinterp/operators/op-fm-fcs.cc, libinterp/operators/op-fm-fm.cc, libinterp/operators/op-fm-fs.cc, libinterp/operators/op-fs-fcm.cc, libinterp/operators/op-fs-fcs.cc, libinterp/operators/op-fs-fm.cc, libinterp/operators/op-fs-fs.cc, libinterp/operators/op-m-cm.cc, libinterp/operators/op-m-cs.cc, libinterp/operators/op-m-m.cc, libinterp/operators/op-m-s.cc, libinterp/operators/op-m-scm.cc, libinterp/operators/op-m-sm.cc, libinterp/operators/op-pm-scm.cc, libinterp/operators/op-range.cc, libinterp/operators/op-s-cm.cc, libinterp/operators/op-s-cs.cc, libinterp/operators/op-s-scm.cc, libinterp/operators/op-sbm-b.cc, libinterp/operators/op-sbm-bm.cc, libinterp/operators/op-sbm-sbm.cc, libinterp/operators/op-scm-cm.cc, libinterp/operators/op-scm-cs.cc, libinterp/operators/op-scm-m.cc, libinterp/operators/op-scm-s.cc, libinterp/operators/op-scm-scm.cc, libinterp/operators/op-scm-sm.cc, libinterp/operators/op-sm-cm.cc, libinterp/operators/op-sm-m.cc, libinterp/operators/op-sm-s.cc, libinterp/operators/op-sm-scm.cc, libinterp/operators/op-sm-sm.cc, libinterp/operators/op-str-m.cc, libinterp/operators/op-str-s.cc, libinterp/operators/op-str-str.cc, libinterp/operators/ops.h, libinterp/parse-tree/lex.h, libinterp/parse-tree/parse.h, libinterp/parse-tree/pt-arg-list.cc, libinterp/parse-tree/pt-arg-list.h, libinterp/parse-tree/pt-assign.cc, libinterp/parse-tree/pt-assign.h, libinterp/parse-tree/pt-binop.cc, libinterp/parse-tree/pt-binop.h, libinterp/parse-tree/pt-bp.h, libinterp/parse-tree/pt-cbinop.cc, libinterp/parse-tree/pt-check.cc, libinterp/parse-tree/pt-colon.cc, libinterp/parse-tree/pt-colon.h, libinterp/parse-tree/pt-const.cc, libinterp/parse-tree/pt-decl.cc, libinterp/parse-tree/pt-decl.h, libinterp/parse-tree/pt-eval.cc, libinterp/parse-tree/pt-except.h, libinterp/parse-tree/pt-exp.h, libinterp/parse-tree/pt-fcn-handle.cc, libinterp/parse-tree/pt-id.cc, libinterp/parse-tree/pt-id.h, libinterp/parse-tree/pt-idx.cc, libinterp/parse-tree/pt-idx.h, libinterp/parse-tree/pt-loop.h, libinterp/parse-tree/pt-mat.cc, libinterp/parse-tree/pt-misc.cc, libinterp/parse-tree/pt-misc.h, libinterp/parse-tree/pt-pr-code.cc, libinterp/parse-tree/pt-select.h, libinterp/parse-tree/pt-stmt.h, libinterp/parse-tree/token.h, libinterp/version.cc: Use GNU style coding conventions for code in libinterp/
author Rik <rik@octave.org>
date Mon, 28 Oct 2013 19:51:46 -0700
parents d63878346099
children 6a71e5030df5 0821a51a9e1b
line wrap: on
line source

/*

Copyright (C) 2004-2013 David Bateman
Copyright (C) 1998-2004 Andy Adler
Copyright (C) 2010 VZLU Prague

This file is part of Octave.

Octave is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

Octave is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cstdlib>
#include <string>

#include "variables.h"
#include "utils.h"
#include "pager.h"
#include "defun.h"
#include "gripes.h"
#include "quit.h"
#include "unwind-prot.h"

#include "ov-re-sparse.h"
#include "ov-cx-sparse.h"
#include "ov-bool-sparse.h"

DEFUN (issparse, args, ,
       "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} issparse (@var{x})\n\
Return true if @var{x} is a sparse matrix.\n\
@seealso{ismatrix}\n\
@end deftypefn")
{
  if (args.length () != 1)
    {
      print_usage ();
      return octave_value ();
    }
  else
    return octave_value (args(0).is_sparse_type ());
}

DEFUN (sparse, args, ,
       "-*- texinfo -*-\n\
@deftypefn  {Built-in Function} {@var{s} =} sparse (@var{a})\n\
@deftypefnx {Built-in Function} {@var{s} =} sparse (@var{i}, @var{j}, @var{sv}, @var{m}, @var{n}, @var{nzmax})\n\
@deftypefnx {Built-in Function} {@var{s} =} sparse (@var{i}, @var{j}, @var{sv})\n\
@deftypefnx {Built-in Function} {@var{s} =} sparse (@var{i}, @var{j}, @var{s}, @var{m}, @var{n}, \"unique\")\n\
@deftypefnx {Built-in Function} {@var{s} =} sparse (@var{m}, @var{n})\n\
Create a sparse matrix from the full matrix or row, column, value triplets.\n\
If @var{a} is a full matrix, convert it to a sparse matrix representation,\n\
removing all zero values in the process.\n\
\n\
Given the integer index vectors @var{i} and @var{j}, a 1-by-@code{nnz} vector\n\
of real of complex values @var{sv}, overall dimensions @var{m} and @var{n}\n\
of the sparse matrix.  The argument @code{nzmax} is ignored but accepted for\n\
compatibility with @sc{matlab}.  If @var{m} or @var{n} are not specified\n\
their values are derived from the maximum index in the vectors @var{i} and\n\
@var{j} as given by @code{@var{m} = max (@var{i})},\n\
@code{@var{n} = max (@var{j})}.\n\
\n\
@strong{Note}: if multiple values are specified with the same\n\
@var{i}, @var{j} indices, the corresponding values in @var{s} will\n\
be added.  See @code{accumarray} for an example of how to produce different\n\
behavior, such as taking the minimum instead.\n\
\n\
The following are all equivalent:\n\
\n\
@example\n\
@group\n\
s = sparse (i, j, s, m, n)\n\
s = sparse (i, j, s, m, n, \"summation\")\n\
s = sparse (i, j, s, m, n, \"sum\")\n\
@end group\n\
@end example\n\
\n\
Given the option @qcode{\"unique\"}, if more than two values are specified\n\
for the same @var{i}, @var{j} indices, the last specified value will be\n\
used.\n\
\n\
@code{sparse (@var{m}, @var{n})} is equivalent to\n\
@code{sparse ([], [], [], @var{m}, @var{n}, 0)}\n\
\n\
If any of @var{sv}, @var{i} or @var{j} are scalars, they are expanded\n\
to have a common size.\n\
@seealso{full, accumarray}\n\
@end deftypefn")
{
  octave_value retval;
  int nargin = args.length ();

  // Temporarily disable sparse_auto_mutate if set (it's obsolete anyway).
  unwind_protect frame;
  frame.protect_var (Vsparse_auto_mutate);
  Vsparse_auto_mutate = false;

  if (nargin == 1)
    {
      octave_value arg = args (0);
      if (arg.is_bool_type ())
        retval = arg.sparse_bool_matrix_value ();
      else if (arg.is_complex_type ())
        retval = arg.sparse_complex_matrix_value ();
      else if (arg.is_numeric_type ())
        retval = arg.sparse_matrix_value ();
      else
        gripe_wrong_type_arg ("sparse", arg);
    }
  else if (nargin == 2)
    {
      octave_idx_type m = 0, n = 0;
      if (args(0).is_scalar_type () && args(1).is_scalar_type ())
        {
          m = args(0).idx_type_value ();
          n = args(1).idx_type_value ();
        }
      else
        error ("sparse: dimensions M,N must be scalar");

      if (! error_state)
        {
          if (m >= 0 && n >= 0)
            retval = SparseMatrix (m, n);
          else
            error ("sparse: dimensions M,N must be positive or zero");
        }
    }
  else if (nargin >= 3)
    {
      bool summation = true;
      if (nargin > 3 && args(nargin-1).is_string ())
        {
          std::string opt = args(nargin-1).string_value ();
          if (opt == "unique")
            summation = false;
          else if (opt == "sum" || opt == "summation")
            summation = true;
          else
            error ("sparse: invalid option: %s", opt.c_str ());

          nargin -= 1;
        }

      if (! error_state)
        {
          octave_idx_type m = -1, n = -1, nzmax = -1;
          if (nargin == 6)
            {
              nzmax = args(5).idx_type_value ();
              nargin --;
            }

          if (nargin == 5)
            {
              if (args(3).is_scalar_type () && args(4).is_scalar_type ())
                {
                  m = args(3).idx_type_value ();
                  n = args(4).idx_type_value ();
                }
              else
                error ("sparse: expecting scalar dimensions");


              if (! error_state && (m < 0 || n < 0))
                error ("sparse: dimensions must be non-negative");
            }
          else if (nargin != 3)
            print_usage ();

          if (! error_state)
            {
              idx_vector i = args(0).index_vector ();
              idx_vector j = args(1).index_vector ();

              if (args(2).is_bool_type ())
                retval = SparseBoolMatrix (args(2).bool_array_value (), i, j,
                                           m, n, summation, nzmax);
              else if (args(2).is_complex_type ())
                retval = SparseComplexMatrix (args(2).complex_array_value (),
                                              i, j, m, n, summation, nzmax);
              else if (args(2).is_numeric_type ())
                retval = SparseMatrix (args(2).array_value (), i, j,
                                       m, n, summation, nzmax);
              else
                gripe_wrong_type_arg ("sparse", args(2));
            }

        }
    }

  return retval;
}

DEFUN (spalloc, args, ,
       "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {@var{s} =} spalloc (@var{m}, @var{n}, @var{nz})\n\
Create an @var{m}-by-@var{n} sparse matrix with pre-allocated space for at\n\
most @var{nz} nonzero elements.  This is useful for building the matrix\n\
incrementally by a sequence of indexed assignments.  Subsequent indexed\n\
assignments will reuse the pre-allocated memory, provided they are of one of\n\
the simple forms\n\
\n\
@itemize\n\
@item @code{@var{s}(I:J) = @var{x}}\n\
\n\
@item @code{@var{s}(:,I:J) = @var{x}}\n\
\n\
@item @code{@var{s}(K:L,I:J) = @var{x}}\n\
@end itemize\n\
\n\
@b{and} that the following conditions are met:\n\
\n\
@itemize\n\
@item the assignment does not decrease nnz (@var{S}).\n\
\n\
@item after the assignment, nnz (@var{S}) does not exceed @var{nz}.\n\
\n\
@item no index is out of bounds.\n\
@end itemize\n\
\n\
Partial movement of data may still occur, but in general the assignment will\n\
be more memory and time-efficient under these circumstances.  In particular,\n\
it is possible to efficiently build a pre-allocated sparse matrix from\n\
contiguous block of columns.\n\
\n\
The amount of pre-allocated memory for a given matrix may be queried using\n\
the function @code{nzmax}.\n\
@seealso{nzmax, sparse}\n\
@end deftypefn")
{
  octave_value retval;
  int nargin = args.length ();

  if (nargin == 2 || nargin == 3)
    {
      octave_idx_type m = args(0).idx_type_value ();
      octave_idx_type n = args(1).idx_type_value ();
      octave_idx_type nz = 0;
      if (nargin == 3)
        nz = args(2).idx_type_value ();
      if (error_state)
        ;
      else if (m >= 0 && n >= 0 && nz >= 0)
        retval = SparseMatrix (dim_vector (m, n), nz);
      else
        error ("spalloc: M,N,NZ must be non-negative");
    }
  else
    print_usage ();

  return retval;
}