Mercurial > octave
view libinterp/corefcn/sqrtm.cc @ 21200:fcac5dbbf9ed
maint: Indent #ifdef blocks in libinterp.
* builtins.h, Cell.cc, __contourc__.cc, __dispatch__.cc, __dsearchn__.cc,
__ichol__.cc, __ilu__.cc, __lin_interpn__.cc, __pchip_deriv__.cc, __qp__.cc,
balance.cc, besselj.cc, betainc.cc, bitfcns.cc, bsxfun.cc,
c-file-ptr-stream.cc, c-file-ptr-stream.h, cellfun.cc, colloc.cc,
comment-list.cc, conv2.cc, daspk.cc, dasrt.cc, dassl.cc, data.cc, debug.cc,
defaults.cc, defaults.in.h, defun-dld.h, defun.cc, defun.h, det.cc, dirfns.cc,
display.cc, dlmread.cc, dot.cc, dynamic-ld.cc, eig.cc, ellipj.cc, error.cc,
errwarn.cc, event-queue.cc, fft.cc, fft2.cc, fftn.cc, file-io.cc, filter.cc,
find.cc, gammainc.cc, gcd.cc, getgrent.cc, getpwent.cc, getrusage.cc,
givens.cc, gl-render.cc, gl2ps-print.cc, graphics.cc, graphics.in.h, gripes.cc,
hash.cc, help.cc, hess.cc, hex2num.cc, input.cc, inv.cc, jit-ir.cc,
jit-typeinfo.cc, jit-util.cc, jit-util.h, kron.cc, load-path.cc, load-save.cc,
lookup.cc, ls-ascii-helper.cc, ls-hdf5.cc, ls-mat-ascii.cc, ls-mat4.cc,
ls-mat5.cc, ls-oct-binary.cc, ls-oct-text.cc, ls-oct-text.h, ls-utils.cc,
ls-utils.h, lsode.cc, lu.cc, luinc.cc, mappers.cc, matrix_type.cc, max.cc,
mex.h, mexproto.h, mgorth.cc, nproc.cc, oct-errno.in.cc, oct-fstrm.cc,
oct-hdf5-types.cc, oct-hdf5.h, oct-hist.cc, oct-iostrm.cc, oct-lvalue.cc,
oct-map.cc, oct-prcstrm.cc, oct-procbuf.cc, oct-stream.cc, oct-strstrm.cc,
octave-link.cc, ordschur.cc, pager.cc, pinv.cc, pr-output.cc, procstream.cc,
profiler.cc, psi.cc, pt-jit.cc, quad.cc, quadcc.cc, qz.cc, rand.cc, rcond.cc,
regexp.cc, schur.cc, sighandlers.cc, sparse-xdiv.cc, sparse-xpow.cc, sparse.cc,
spparms.cc, sqrtm.cc, str2double.cc, strfind.cc, strfns.cc, sub2ind.cc, svd.cc,
sylvester.cc, symtab.cc, syscalls.cc, sysdep.cc, sysdep.h, time.cc, toplev.cc,
tril.cc, tsearch.cc, txt-eng-ft.cc, txt-eng.cc, typecast.cc, urlwrite.cc,
utils.cc, variables.cc, xdiv.cc, xnorm.cc, xpow.cc, zfstream.cc,
__delaunayn__.cc, __eigs__.cc, __fltk_uigetfile__.cc, __glpk__.cc,
__init_fltk__.cc, __init_gnuplot__.cc, __magick_read__.cc, __osmesa_print__.cc,
__voronoi__.cc, amd.cc, audiodevinfo.cc, audioread.cc, ccolamd.cc, chol.cc,
colamd.cc, convhulln.cc, dmperm.cc, fftw.cc, oct-qhull.h, qr.cc, symbfact.cc,
symrcm.cc, oct-conf.in.cc, ov-base-diag.cc, ov-base-int.cc, ov-base-mat.cc,
ov-base-scalar.cc, ov-base-sparse.cc, ov-base.cc, ov-bool-mat.cc,
ov-bool-sparse.cc, ov-bool.cc, ov-builtin.cc, ov-cell.cc, ov-ch-mat.cc,
ov-class.cc, ov-classdef.cc, ov-colon.cc, ov-complex.cc, ov-cs-list.cc,
ov-cx-diag.cc, ov-cx-mat.cc, ov-cx-sparse.cc, ov-dld-fcn.cc, ov-fcn-handle.cc,
ov-fcn-inline.cc, ov-fcn.cc, ov-float.cc, ov-flt-complex.cc, ov-flt-cx-diag.cc,
ov-flt-cx-mat.cc, ov-flt-re-diag.cc, ov-flt-re-mat.cc, ov-int16.cc,
ov-int32.cc, ov-int64.cc, ov-int8.cc, ov-java.cc, ov-lazy-idx.cc,
ov-mex-fcn.cc, ov-null-mat.cc, ov-oncleanup.cc, ov-perm.cc, ov-range.cc,
ov-re-diag.cc, ov-re-mat.cc, ov-re-sparse.cc, ov-scalar.cc, ov-str-mat.cc,
ov-struct.cc, ov-typeinfo.cc, ov-uint16.cc, ov-uint32.cc, ov-uint64.cc,
ov-uint8.cc, ov-usr-fcn.cc, ov.cc, ovl.cc, octave.cc, op-b-b.cc, op-b-bm.cc,
op-b-sbm.cc, op-bm-b.cc, op-bm-bm.cc, op-bm-sbm.cc, op-cdm-cdm.cc, op-cell.cc,
op-chm.cc, op-class.cc, op-cm-cm.cc, op-cm-cs.cc, op-cm-m.cc, op-cm-s.cc,
op-cm-scm.cc, op-cm-sm.cc, op-cs-cm.cc, op-cs-cs.cc, op-cs-m.cc, op-cs-s.cc,
op-cs-scm.cc, op-cs-sm.cc, op-dm-dm.cc, op-dm-scm.cc, op-dm-sm.cc,
op-dm-template.cc, op-dms-template.cc, op-double-conv.cc, op-fcdm-fcdm.cc,
op-fcdm-fdm.cc, op-fcm-fcm.cc, op-fcm-fcs.cc, op-fcm-fm.cc, op-fcm-fs.cc,
op-fcn.cc, op-fcs-fcm.cc, op-fcs-fcs.cc, op-fcs-fm.cc, op-fcs-fs.cc,
op-fdm-fdm.cc, op-float-conv.cc, op-fm-fcm.cc, op-fm-fcs.cc, op-fm-fm.cc,
op-fm-fs.cc, op-fs-fcm.cc, op-fs-fcs.cc, op-fs-fm.cc, op-fs-fs.cc,
op-i16-i16.cc, op-i32-i32.cc, op-i64-i64.cc, op-i8-i8.cc, op-int-concat.cc,
op-int-conv.cc, op-m-cm.cc, op-m-cs.cc, op-m-m.cc, op-m-s.cc, op-m-scm.cc,
op-m-sm.cc, op-pm-pm.cc, op-pm-scm.cc, op-pm-sm.cc, op-pm-template.cc,
op-range.cc, op-s-cm.cc, op-s-cs.cc, op-s-m.cc, op-s-s.cc, op-s-scm.cc,
op-s-sm.cc, op-sbm-b.cc, op-sbm-bm.cc, op-sbm-sbm.cc, op-scm-cm.cc,
op-scm-cs.cc, op-scm-m.cc, op-scm-s.cc, op-scm-scm.cc, op-scm-sm.cc,
op-sm-cm.cc, op-sm-cs.cc, op-sm-m.cc, op-sm-s.cc, op-sm-scm.cc, op-sm-sm.cc,
op-str-m.cc, op-str-s.cc, op-str-str.cc, op-struct.cc, op-ui16-ui16.cc,
op-ui32-ui32.cc, op-ui64-ui64.cc, op-ui8-ui8.cc, pt-arg-list.cc,
pt-array-list.cc, pt-assign.cc, pt-binop.cc, pt-bp.cc, pt-cbinop.cc,
pt-cell.cc, pt-check.cc, pt-classdef.cc, pt-cmd.cc, pt-colon.cc, pt-colon.h,
pt-const.cc, pt-decl.cc, pt-eval.cc, pt-except.cc, pt-exp.cc, pt-fcn-handle.cc,
pt-funcall.cc, pt-id.cc, pt-idx.cc, pt-jump.cc, pt-loop.cc, pt-mat.cc,
pt-misc.cc, pt-pr-code.cc, pt-select.cc, pt-stmt.cc, pt-unop.cc, pt.cc,
token.cc, Array-jit.cc, Array-os.cc, Array-sym.cc, Array-tc.cc, version.cc:
Indent #ifdef blocks in libinterp.
author | Rik <rik@octave.org> |
---|---|
date | Fri, 05 Feb 2016 16:29:08 -0800 |
parents | 538b57866b90 |
children | e69eaee28737 |
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/* Copyright (C) 2001-2015 Ross Lippert and Paul Kienzle 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 <float.h> #include "CmplxSCHUR.h" #include "fCmplxSCHUR.h" #include "lo-ieee.h" #include "lo-mappers.h" #include "oct-norm.h" #include "defun.h" #include "error.h" #include "errwarn.h" #include "utils.h" #include "xnorm.h" template <typename Matrix> static void sqrtm_utri_inplace (Matrix& T) { typedef typename Matrix::element_type element_type; const element_type zero = element_type (); bool singular = false; // The following code is equivalent to this triple loop: // // n = rows (T); // for j = 1:n // T(j,j) = sqrt (T(j,j)); // for i = j-1:-1:1 // T(i,j) /= (T(i,i) + T(j,j)); // k = 1:i-1; // T(k,j) -= T(k,i) * T(i,j); // endfor // endfor // // this is an in-place, cache-aligned variant of the code // given in Higham's paper. const octave_idx_type n = T.rows (); element_type *Tp = T.fortran_vec (); for (octave_idx_type j = 0; j < n; j++) { element_type *colj = Tp + n*j; if (colj[j] != zero) colj[j] = sqrt (colj[j]); else singular = true; for (octave_idx_type i = j-1; i >= 0; i--) { const element_type *coli = Tp + n*i; const element_type colji = colj[i] /= (coli[i] + colj[j]); for (octave_idx_type k = 0; k < i; k++) colj[k] -= coli[k] * colji; } } if (singular) warning_with_id ("Octave:sqrtm:SingularMatrix", "sqrtm: matrix is singular, may not have a square root"); } template <typename Matrix, typename ComplexMatrix, typename ComplexSCHUR> static octave_value do_sqrtm (const octave_value& arg) { octave_value retval; MatrixType mt = arg.matrix_type (); bool iscomplex = arg.is_complex_type (); typedef typename Matrix::element_type real_type; real_type cutoff = 0; real_type one = 1; real_type eps = std::numeric_limits<real_type>::epsilon (); if (! iscomplex) { Matrix x = octave_value_extract<Matrix> (arg); if (mt.is_unknown ()) // if type is not known, compute it now. arg.matrix_type (mt = MatrixType (x)); switch (mt.type ()) { case MatrixType::Upper: case MatrixType::Diagonal: if (! x.diag ().any_element_is_negative ()) { // Do it in real arithmetic. sqrtm_utri_inplace (x); retval = x; retval.matrix_type (mt); } else iscomplex = true; break; case MatrixType::Lower: if (! x.diag ().any_element_is_negative ()) { x = x.transpose (); sqrtm_utri_inplace (x); retval = x.transpose (); retval.matrix_type (mt); } else iscomplex = true; break; default: iscomplex = true; break; } if (iscomplex) cutoff = 10 * x.rows () * eps * xnorm (x, one); } if (iscomplex) { ComplexMatrix x = octave_value_extract<ComplexMatrix> (arg); if (mt.is_unknown ()) // if type is not known, compute it now. arg.matrix_type (mt = MatrixType (x)); switch (mt.type ()) { case MatrixType::Upper: case MatrixType::Diagonal: sqrtm_utri_inplace (x); retval = x; retval.matrix_type (mt); break; case MatrixType::Lower: x = x.transpose (); sqrtm_utri_inplace (x); retval = x.transpose (); retval.matrix_type (mt); break; default: { ComplexMatrix u; do { ComplexSCHUR schur (x, "", true); x = schur.schur_matrix (); u = schur.unitary_matrix (); } while (0); // schur no longer needed. sqrtm_utri_inplace (x); x = u * x; // original x no longer needed. ComplexMatrix res = xgemm (x, u, blas_no_trans, blas_conj_trans); if (cutoff > 0 && xnorm (imag (res), one) <= cutoff) retval = real (res); else retval = res; } break; } } return retval; } DEFUN (sqrtm, args, nargout, "-*- texinfo -*-\n\ @deftypefn {} {@var{s} =} sqrtm (@var{A})\n\ @deftypefnx {} {[@var{s}, @var{error_estimate}] =} sqrtm (@var{A})\n\ Compute the matrix square root of the square matrix @var{A}.\n\ \n\ Ref: @nospell{N.J. Higham}. @cite{A New sqrtm for @sc{matlab}}. Numerical\n\ Analysis Report No. 336, Manchester @nospell{Centre} for Computational\n\ Mathematics, Manchester, England, January 1999.\n\ @seealso{expm, logm}\n\ @end deftypefn") { if (args.length () != 1) print_usage (); octave_value arg = args(0); octave_idx_type n = arg.rows (); octave_idx_type nc = arg.columns (); if (n != nc || arg.ndims () > 2) err_square_matrix_required ("sqrtm", "A"); octave_value_list retval (nargout > 1 ? 3 : 1); if (nargout > 1) { // FIXME: Octave does not calculate a condition number with respect to // sqrtm. Should this return NaN instead of -1? retval(2) = -1.0; } if (arg.is_diag_matrix ()) // sqrtm of a diagonal matrix is just sqrt. retval(0) = arg.sqrt (); else if (arg.is_single_type ()) retval(0) = do_sqrtm<FloatMatrix, FloatComplexMatrix, FloatComplexSCHUR> (arg); else if (arg.is_numeric_type ()) retval(0) = do_sqrtm<Matrix, ComplexMatrix, ComplexSCHUR> (arg); if (nargout > 1) { // This corresponds to generic code // // norm (s*s - x, "fro") / norm (x, "fro"); octave_value s = retval(0); retval(1) = xfrobnorm (s*s - arg) / xfrobnorm (arg); } return retval; } /* %!assert (sqrtm (2*ones (2)), ones (2), 3*eps) ## The following two tests are from the reference in the docstring above. %!test %! x = [0 1; 0 0]; %! assert (any (isnan (sqrtm (x))(:))); %!test %! x = eye (4); x(2,2) = x(3,3) = 2^-26; x(1,4) = 1; %! z = eye (4); z(2,2) = z(3,3) = 2^-13; z(1,4) = 0.5; %! [y, err] = sqrtm (x); %! assert (y, z); %! assert (err, 0); # Yes, this one has to hold exactly */