ov-flt-re-mat.cc

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////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 1996-2024 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// 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
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////
 
#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif
 
#include <clocale>
#include <istream>
#include <limits>
#include <ostream>
#include <vector>
 
#include "dNDArray.h"
#include "fNDArray.h"
#include "int8NDArray.h"
#include "int16NDArray.h"
#include "int32NDArray.h"
#include "int64NDArray.h"
#include "uint8NDArray.h"
#include "uint16NDArray.h"
#include "uint32NDArray.h"
#include "uint64NDArray.h"
 
#include "data-conv.h"
#include "lo-ieee.h"
#include "lo-utils.h"
#include "lo-specfun.h"
#include "lo-mappers.h"
#include "mach-info.h"
#include "mx-base.h"
#include "quit.h"
#include "oct-locbuf.h"
 
#include "defun.h"
#include "errwarn.h"
#include "mxarray.h"
#include "ovl.h"
#include "oct-lvalue.h"
#include "oct-hdf5.h"
#include "oct-stream.h"
#include "ops.h"
#include "ov-base.h"
#include "ov-base-mat.h"
#include "ov-base-mat.cc"
#include "ov-scalar.h"
#include "ov-float.h"
#include "ov-flt-complex.h"
#include "ov-re-mat.h"
#include "ov-flt-re-mat.h"
#include "ov-flt-cx-mat.h"
#include "ov-re-sparse.h"
#include "ov-flt-re-diag.h"
#include "ov-flt-cx-diag.h"
#include "pr-output.h"
#include "variables.h"
#include "ops.h"
 
#include "byte-swap.h"
#include "ls-oct-text.h"
#include "ls-utils.h"
#include "ls-hdf5.h"
 
 
template class octave_base_matrix<FloatNDArray>;
 
DEFINE_OV_TYPEID_FUNCTIONS_AND_DATA (octave_float_matrix, "float matrix",
                                     "single");
 
octave_base_value *
octave_float_matrix::try_narrowing_conversion ()
{
  octave_base_value *retval = nullptr;
 
  if (m_matrix.numel () == 1)
    retval = new octave_float_scalar (m_matrix (0));
 
  return retval;
}
 
double
octave_float_matrix::double_value (bool) const
{
  if (isempty ())
    err_invalid_conversion ("real matrix", "real scalar");
 
  warn_implicit_conversion ("Octave:array-to-scalar",
                            "real matrix", "real scalar");
 
  return m_matrix(0, 0);
}
 
float
octave_float_matrix::float_value (bool) const
{
  if (isempty ())
    err_invalid_conversion ("real matrix", "real scalar");
 
  warn_implicit_conversion ("Octave:array-to-scalar",
                            "real matrix", "real scalar");
 
  return m_matrix(0, 0);
}
 
// FIXME
 
Matrix
octave_float_matrix::matrix_value (bool) const
{
  return Matrix (FloatMatrix (m_matrix));
}
 
FloatMatrix
octave_float_matrix::float_matrix_value (bool) const
{
  return FloatMatrix (m_matrix);
}
 
Complex
octave_float_matrix::complex_value (bool) const
{
  if (rows () == 0 || columns () == 0)
    err_invalid_conversion ("real matrix", "complex scalar");
 
  warn_implicit_conversion ("Octave:array-to-scalar",
                            "real matrix", "complex scalar");
 
  return Complex (m_matrix(0, 0), 0);
}
 
FloatComplex
octave_float_matrix::float_complex_value (bool) const
{
  double tmp = lo_ieee_float_nan_value ();
 
  FloatComplex retval (tmp, tmp);
 
  if (rows () == 0 || columns () == 0)
    err_invalid_conversion ("real matrix", "complex scalar");
 
  warn_implicit_conversion ("Octave:array-to-scalar",
                            "real matrix", "complex scalar");
 
  retval = m_matrix(0, 0);
 
  return retval;
}
 
// FIXME
 
ComplexMatrix
octave_float_matrix::complex_matrix_value (bool) const
{
  return ComplexMatrix (FloatMatrix (m_matrix));
}
 
FloatComplexMatrix
octave_float_matrix::float_complex_matrix_value (bool) const
{
  return FloatComplexMatrix (FloatMatrix (m_matrix));
}
 
ComplexNDArray
octave_float_matrix::complex_array_value (bool) const
{
  return ComplexNDArray (m_matrix);
}
 
FloatComplexNDArray
octave_float_matrix::float_complex_array_value (bool) const
{
  return FloatComplexNDArray (m_matrix);
}
 
NDArray
octave_float_matrix::array_value (bool) const
{
  return NDArray (m_matrix);
}
 
boolNDArray
octave_float_matrix::bool_array_value (bool warn) const
{
  if (m_matrix.any_element_is_nan ())
    octave::err_nan_to_logical_conversion ();
  if (warn && m_matrix.any_element_not_one_or_zero ())
    warn_logical_conversion ();
 
  return boolNDArray (m_matrix);
}
 
charNDArray
octave_float_matrix::char_array_value (bool) const
{
  charNDArray retval (dims ());
 
  octave_idx_type nel = numel ();
 
  for (octave_idx_type i = 0; i < nel; i++)
    retval.elem (i) = static_cast<char> (m_matrix.elem (i));
 
  return retval;
}
 
SparseMatrix
octave_float_matrix::sparse_matrix_value (bool) const
{
  return SparseMatrix (matrix_value ());
}
 
SparseComplexMatrix
octave_float_matrix::sparse_complex_matrix_value (bool) const
{
  // FIXME: Need a SparseComplexMatrix (Matrix) constructor to make
  // this function more efficient.  Then this should become
  // return SparseComplexMatrix (matrix.matrix_value ());
  return SparseComplexMatrix (sparse_matrix_value ());
}
 
octave_value
octave_float_matrix::as_double () const
{
  return NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_single () const
{
  return FloatNDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_int8 () const
{
  return int8NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_int16 () const
{
  return int16NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_int32 () const
{
  return int32NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_int64 () const
{
  return int64NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_uint8 () const
{
  return uint8NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_uint16 () const
{
  return uint16NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_uint32 () const
{
  return uint32NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::as_uint64 () const
{
  return uint64NDArray (m_matrix);
}
 
octave_value
octave_float_matrix::diag (octave_idx_type k) const
{
  octave_value retval;
  if (k == 0 && m_matrix.ndims () == 2
      && (m_matrix.rows () == 1 || m_matrix.columns () == 1))
    retval = FloatDiagMatrix (DiagArray2<float> (m_matrix));
  else
    retval = octave_base_matrix<FloatNDArray>::diag (k);
 
  return retval;
}
 
octave_value
octave_float_matrix::diag (octave_idx_type m, octave_idx_type n) const
{
  if (m_matrix.ndims () != 2
      || (m_matrix.rows () != 1 && m_matrix.columns () != 1))
    error ("diag: expecting vector argument");
 
  FloatMatrix mat (m_matrix);
 
  return mat.diag (m, n);
}
 
octave_value
octave_float_matrix::convert_to_str_internal (bool, bool, char type) const
{
  octave_value retval;
  dim_vector dv = dims ();
  octave_idx_type nel = dv.numel ();
 
  charNDArray chm (dv);
 
  bool warned = false;
 
  for (octave_idx_type i = 0; i < nel; i++)
    {
      octave_quit ();
 
      float d = m_matrix(i);
 
      if (octave::math::isnan (d))
        octave::err_nan_to_character_conversion ();
 
      int ival = octave::math::nint (d);
 
      if (ival < 0 || ival > std::numeric_limits<unsigned char>::max ())
        {
          // FIXME: is there something better we could do?
 
          ival = 0;
 
          if (! warned)
            {
              ::warning ("range error for conversion to character value");
              warned = true;
            }
        }
 
      chm(i) = static_cast<char> (ival);
    }
 
  retval = octave_value (chm, type);
 
  return retval;
}
 
bool
octave_float_matrix::save_ascii (std::ostream& os)
{
  dim_vector dv = dims ();
 
  if (dv.ndims () > 2)
    {
      FloatNDArray tmp = float_array_value ();
 
      os << "# ndims: " << dv.ndims () << "\n";
 
      for (int i=0; i < dv.ndims (); i++)
        os << ' ' << dv(i);
 
      os << "\n" << tmp;
    }
  else
    {
      // Keep this case, rather than use generic code above for backward
      // compatibility.  Makes load_ascii much more complex!!
      os << "# rows: " << rows () << "\n"
         << "# columns: " << columns () << "\n";
 
      os << float_matrix_value ();
    }
 
  return true;
}
 
bool
octave_float_matrix::load_ascii (std::istream& is)
{
  string_vector keywords(2);
 
  keywords[0] = "ndims";
  keywords[1] = "rows";
 
  std::string kw;
  octave_idx_type val = 0;
 
  if (! extract_keyword (is, keywords, kw, val, true))
    error ("load: failed to extract number of rows and columns");
 
  // Set "C" locale for the duration of this function to avoid the performance
  // panelty of frequently switching the locale when reading floating point
  // values from the stream.
  char *prev_locale = std::setlocale (LC_ALL, nullptr);
  std::string old_locale (prev_locale ? prev_locale : "");
  std::setlocale (LC_ALL, "C");
  octave::unwind_action act
  ([&old_locale] () { std::setlocale (LC_ALL, old_locale.c_str ()); });
 
  if (kw == "ndims")
    {
      int mdims = static_cast<int> (val);
 
      if (mdims < 0)
        error ("load: failed to extract number of dimensions");
 
      dim_vector dv;
      dv.resize (mdims);
 
      for (int i = 0; i < mdims; i++)
        is >> dv(i);
 
      if (! is)
        error ("load: failed to read dimensions");
 
      FloatNDArray tmp(dv);
 
      is >> tmp;
 
      if (! is)
        error ("load: failed to load matrix constant");
 
      m_matrix = tmp;
    }
  else if (kw == "rows")
    {
      octave_idx_type nr = val;
      octave_idx_type nc = 0;
 
      if (nr < 0 || ! extract_keyword (is, "columns", nc) || nc < 0)
        error ("load: failed to extract number of rows and columns");
 
      if (nr > 0 && nc > 0)
        {
          FloatMatrix tmp (nr, nc);
          is >> tmp;
          if (! is)
            error ("load: failed to load matrix constant");
 
          m_matrix = tmp;
        }
      else if (nr == 0 || nc == 0)
        m_matrix = FloatMatrix (nr, nc);
      else
        panic_impossible ();
    }
  else
    panic_impossible ();
 
  return true;
}
 
bool
octave_float_matrix::save_binary (std::ostream& os, bool)
{
  dim_vector dv = dims ();
  if (dv.ndims () < 1)
    return false;
 
  // Use negative value for ndims to differentiate with old format!!
  int32_t tmp = - dv.ndims ();
  os.write (reinterpret_cast<char *> (&tmp), 4);
  for (int i = 0; i < dv.ndims (); i++)
    {
      tmp = dv(i);
      os.write (reinterpret_cast<char *> (&tmp), 4);
    }
 
  FloatNDArray m = float_array_value ();
  save_type st = LS_FLOAT;
  if (dv.numel () > 8192) // FIXME: make this configurable.
    {
      float max_val, min_val;
      if (m.all_integers (max_val, min_val))
        st = octave::get_save_type (max_val, min_val);
    }
 
  const float *mtmp = m.data ();
  write_floats (os, mtmp, st, dv.numel ());
 
  return true;
}
 
bool
octave_float_matrix::load_binary (std::istream& is, bool swap,
                                  octave::mach_info::float_format fmt)
{
  char tmp;
  int32_t mdims;
  if (! is.read (reinterpret_cast<char *> (&mdims), 4))
    return false;
  if (swap)
    swap_bytes<4> (&mdims);
  if (mdims < 0)
    {
      mdims = - mdims;
      int32_t di;
      dim_vector dv;
      dv.resize (mdims);
 
      for (int i = 0; i < mdims; i++)
        {
          if (! is.read (reinterpret_cast<char *> (&di), 4))
            return false;
          if (swap)
            swap_bytes<4> (&di);
          dv(i) = di;
        }
 
      // Convert an array with a single dimension to be a row vector.
      // Octave should never write files like this, other software
      // might.
 
      if (mdims == 1)
        {
          mdims = 2;
          dv.resize (mdims);
          dv(1) = dv(0);
          dv(0) = 1;
        }
 
      if (! is.read (reinterpret_cast<char *> (&tmp), 1))
        return false;
 
      FloatNDArray m(dv);
      float *re = m.fortran_vec ();
      read_floats (is, re, static_cast<save_type> (tmp), dv.numel (),
                   swap, fmt);
 
      if (! is)
        return false;
 
      m_matrix = m;
    }
  else
    {
      int32_t nr, nc;
      nr = mdims;
      if (! is.read (reinterpret_cast<char *> (&nc), 4))
        return false;
      if (swap)
        swap_bytes<4> (&nc);
      if (! is.read (reinterpret_cast<char *> (&tmp), 1))
        return false;
      FloatMatrix m (nr, nc);
      float *re = m.fortran_vec ();
      octave_idx_type len = static_cast<octave_idx_type> (nr) * nc;
      read_floats (is, re, static_cast<save_type> (tmp), len, swap, fmt);
 
      if (! is)
        return false;
 
      m_matrix = m;
    }
  return true;
}
 
bool
octave_float_matrix::save_hdf5 (octave_hdf5_id loc_id, const char *name, bool)
{
  bool retval = false;
 
#if defined (HAVE_HDF5)
 
  dim_vector dv = dims ();
  int empty = save_hdf5_empty (loc_id, name, dv);
  if (empty)
    return (empty > 0);
 
  int rank = dv.ndims ();
  hid_t space_hid, data_hid;
  space_hid = data_hid = -1;
  FloatNDArray m = array_value ();
 
  OCTAVE_LOCAL_BUFFER (hsize_t, hdims, rank);
 
  // Octave uses column-major, while HDF5 uses row-major ordering
  for (int i = 0; i < rank; i++)
    hdims[i] = dv(rank-i-1);
 
  space_hid = H5Screate_simple (rank, hdims, nullptr);
 
  if (space_hid < 0) return false;
 
  hid_t save_type_hid = H5T_NATIVE_FLOAT;
 
#if defined (HAVE_HDF5_INT2FLOAT_CONVERSIONS)
  // hdf5 currently doesn't support float/integer conversions
  else
    {
      float max_val, min_val;
 
      if (m.all_integers (max_val, min_val))
        save_type_hid
          = save_type_to_hdf5 (octave::get_save_type (max_val, min_val));
    }
#endif
#if defined (HAVE_HDF5_18)
  data_hid = H5Dcreate (loc_id, name, save_type_hid, space_hid,
                        octave_H5P_DEFAULT, octave_H5P_DEFAULT,
                        octave_H5P_DEFAULT);
#else
  data_hid = H5Dcreate (loc_id, name, save_type_hid, space_hid,
                        octave_H5P_DEFAULT);
#endif
  if (data_hid < 0)
    {
      H5Sclose (space_hid);
      return false;
    }
 
  const float *mtmp = m.data ();
  retval = H5Dwrite (data_hid, H5T_NATIVE_FLOAT, octave_H5S_ALL, octave_H5S_ALL,
                     octave_H5P_DEFAULT, mtmp) >= 0;
 
  H5Dclose (data_hid);
  H5Sclose (space_hid);
 
#else
  octave_unused_parameter (loc_id);
  octave_unused_parameter (name);
 
  warn_save ("hdf5");
#endif
 
  return retval;
}
 
bool
octave_float_matrix::load_hdf5 (octave_hdf5_id loc_id, const char *name)
{
  bool retval = false;
 
#if defined (HAVE_HDF5)
 
  dim_vector dv;
  int empty = load_hdf5_empty (loc_id, name, dv);
  if (empty > 0)
    m_matrix.resize (dv);
  if (empty)
    return (empty > 0);
 
#if defined (HAVE_HDF5_18)
  hid_t data_hid = H5Dopen (loc_id, name, octave_H5P_DEFAULT);
#else
  hid_t data_hid = H5Dopen (loc_id, name);
#endif
  hid_t space_id = H5Dget_space (data_hid);
 
  hsize_t rank = H5Sget_simple_extent_ndims (space_id);
 
  if (rank < 1)
    {
      H5Sclose (space_id);
      H5Dclose (data_hid);
      return false;
    }
 
  OCTAVE_LOCAL_BUFFER (hsize_t, hdims, rank);
  OCTAVE_LOCAL_BUFFER (hsize_t, maxdims, rank);
 
  H5Sget_simple_extent_dims (space_id, hdims, maxdims);
 
  // Octave uses column-major, while HDF5 uses row-major ordering
  if (rank == 1)
    {
      dv.resize (2);
      dv(0) = 1;
      dv(1) = hdims[0];
    }
  else
    {
      dv.resize (rank);
      for (hsize_t i = 0, j = rank - 1; i < rank; i++, j--)
        dv(j) = hdims[i];
    }
 
  FloatNDArray m (dv);
  float *re = m.fortran_vec ();
  if (H5Dread (data_hid, H5T_NATIVE_FLOAT, octave_H5S_ALL, octave_H5S_ALL,
               octave_H5P_DEFAULT, re) >= 0)
    {
      retval = true;
      m_matrix = m;
    }
 
  H5Sclose (space_id);
  H5Dclose (data_hid);
 
#else
  octave_unused_parameter (loc_id);
  octave_unused_parameter (name);
 
  warn_load ("hdf5");
#endif
 
  return retval;
}
 
void
octave_float_matrix::print_raw (std::ostream& os,
                                bool pr_as_read_syntax) const
{
  octave_print_internal (os, m_matrix, pr_as_read_syntax,
                         current_print_indent_level ());
}
 
mxArray *
octave_float_matrix::as_mxArray (bool interleaved) const
{
  mxArray *retval = new mxArray (interleaved, mxSINGLE_CLASS, dims (), mxREAL);
 
  mxSingle *pd = static_cast<mxSingle *> (retval->get_data ());
 
  mwSize nel = numel ();
 
  const float *pdata = m_matrix.data ();
 
  for (mwIndex i = 0; i < nel; i++)
    pd[i] = pdata[i];
 
  return retval;
}
 
// This uses a smarter strategy for doing the complex->real mappers.  We
// allocate an array for a real result and keep filling it until a complex
// result is produced.
static octave_value
do_rc_map (const FloatNDArray& a, FloatComplex (&fcn) (float))
{
  octave_idx_type n = a.numel ();
  FloatNDArray rr (a.dims ());
 
  for (octave_idx_type i = 0; i < n; i++)
    {
      octave_quit ();
 
      FloatComplex tmp = fcn (a(i));
      if (tmp.imag () == 0.0)
        rr.xelem (i) = tmp.real ();
      else
        {
          FloatComplexNDArray rc (a.dims ());
 
          for (octave_idx_type j = 0; j < i; j++)
            rc.xelem (j) = rr.xelem (j);
 
          rc.xelem (i) = tmp;
 
          for (octave_idx_type j = i+1; j < n; j++)
            {
              octave_quit ();
 
              rc.xelem (j) = fcn (a(j));
            }
 
          return new octave_float_complex_matrix (rc);
        }
    }
 
  return rr;
}
 
octave_value
octave_float_matrix::map (unary_mapper_t umap) const
{
  switch (umap)
    {
    case umap_imag:
      return FloatNDArray (m_matrix.dims (), 0.0);
 
    case umap_real:
    case umap_conj:
      return m_matrix;
 
      // Mappers handled specially.
#define ARRAY_METHOD_MAPPER(UMAP, FCN)        \
    case umap_ ## UMAP:                       \
      return octave_value (m_matrix.FCN ())
 
      ARRAY_METHOD_MAPPER (abs, abs);
      ARRAY_METHOD_MAPPER (isnan, isnan);
      ARRAY_METHOD_MAPPER (isinf, isinf);
      ARRAY_METHOD_MAPPER (isfinite, isfinite);
 
#define ARRAY_MAPPER(UMAP, TYPE, FCN)                 \
    case umap_ ## UMAP:                               \
      return octave_value (m_matrix.map<TYPE> (FCN))
 
#define RC_ARRAY_MAPPER(UMAP, TYPE, FCN)      \
    case umap_ ## UMAP:                       \
      return do_rc_map (m_matrix, FCN)
 
      RC_ARRAY_MAPPER (acos, FloatComplex, octave::math::rc_acos);
      RC_ARRAY_MAPPER (acosh, FloatComplex, octave::math::rc_acosh);
      ARRAY_MAPPER (angle, float, std::arg);
      ARRAY_MAPPER (arg, float, std::arg);
      RC_ARRAY_MAPPER (asin, FloatComplex, octave::math::rc_asin);
      ARRAY_MAPPER (asinh, float, octave::math::asinh);
      ARRAY_MAPPER (atan, float, ::atanf);
      RC_ARRAY_MAPPER (atanh, FloatComplex, octave::math::rc_atanh);
      ARRAY_MAPPER (erf, float, octave::math::erf);
      ARRAY_MAPPER (erfinv, float, octave::math::erfinv);
      ARRAY_MAPPER (erfcinv, float, octave::math::erfcinv);
      ARRAY_MAPPER (erfc, float, octave::math::erfc);
      ARRAY_MAPPER (erfcx, float, octave::math::erfcx);
      ARRAY_MAPPER (erfi, float, octave::math::erfi);
      ARRAY_MAPPER (dawson, float, octave::math::dawson);
      ARRAY_MAPPER (gamma, float, octave::math::gamma);
      RC_ARRAY_MAPPER (lgamma, FloatComplex, octave::math::rc_lgamma);
      ARRAY_MAPPER (cbrt, float, octave::math::cbrt);
      ARRAY_MAPPER (ceil, float, ::ceilf);
      ARRAY_MAPPER (cos, float, ::cosf);
      ARRAY_MAPPER (cosh, float, ::coshf);
      ARRAY_MAPPER (exp, float, ::expf);
      ARRAY_MAPPER (expm1, float, octave::math::expm1);
      ARRAY_MAPPER (fix, float, octave::math::fix);
      ARRAY_MAPPER (floor, float, ::floorf);
      RC_ARRAY_MAPPER (log, FloatComplex, octave::math::rc_log);
      RC_ARRAY_MAPPER (log2, FloatComplex, octave::math::rc_log2);
      RC_ARRAY_MAPPER (log10, FloatComplex, octave::math::rc_log10);
      RC_ARRAY_MAPPER (log1p, FloatComplex, octave::math::rc_log1p);
      ARRAY_MAPPER (round, float, octave::math::round);
      ARRAY_MAPPER (roundb, float, octave::math::roundb);
      ARRAY_MAPPER (signum, float, octave::math::signum);
      ARRAY_MAPPER (sin, float, ::sinf);
      ARRAY_MAPPER (sinh, float, ::sinhf);
      RC_ARRAY_MAPPER (sqrt, FloatComplex, octave::math::rc_sqrt);
      ARRAY_MAPPER (tan, float, ::tanf);
      ARRAY_MAPPER (tanh, float, ::tanhf);
      ARRAY_MAPPER (isna, bool, octave::math::isna);
      ARRAY_MAPPER (xsignbit, float, octave::math::signbit);
 
    // Special cases for Matlab compatibility.
    case umap_xtolower:
    case umap_xtoupper:
      return m_matrix;
 
    case umap_xisalnum:
    case umap_xisalpha:
    case umap_xisascii:
    case umap_xiscntrl:
    case umap_xisdigit:
    case umap_xisgraph:
    case umap_xislower:
    case umap_xisprint:
    case umap_xispunct:
    case umap_xisspace:
    case umap_xisupper:
    case umap_xisxdigit:
      {
        octave_value str_conv = convert_to_str (true, true);
        return str_conv.map (umap);
      }
 
    default:
      return octave_base_value::map (umap);
    }
}