Mercurial > octave
view libinterp/corefcn/givens.cc @ 29654:d13d090cb03a stable
use std::size_t and std::ptrdiff_t in C++ code (bug #60471)
Files affected: make_int.cc, file-editor-tab.cc, octave-qscintilla.cc,
Cell.cc, Cell.h, call-stack.cc, call-stack.h, cellfun.cc, data.cc,
debug.cc, dlmread.cc, error.cc, event-queue.h, fcn-info.cc,
fcn-info.h, file-io.cc, ft-text-renderer.cc, gl2ps-print.cc,
graphics.cc, graphics.in.h, help.cc, hex2num.cc, input.cc,
latex-text-renderer.cc, load-path.cc, load-save.cc, load-save.h,
ls-hdf5.cc, ls-mat-ascii.cc, ls-mat5.cc, ls-oct-text.cc, mex.cc,
mexproto.h, mxarray.h, oct-map.cc, oct-stream.cc, oct-stream.h,
pager.cc, pager.h, pr-output.cc, regexp.cc, settings.h,
stack-frame.cc, stack-frame.h, strfns.cc, syminfo.cc, symrec.h,
symscope.cc, symscope.h, symtab.cc, sysdep.cc, toplev.cc, utils.cc,
utils.h, variables.cc, __fltk_uigetfile__.cc, __init_fltk__.cc,
audioread.cc, gzip.cc, cdef-class.cc, cdef-manager.cc, cdef-method.cc,
cdef-object.cc, cdef-object.h, ov-base-diag.cc, ov-base-diag.h,
ov-base-mat.cc, ov-base-mat.h, ov-base-scalar.cc, ov-base-scalar.h,
ov-base-sparse.h, ov-base.cc, ov-base.h, ov-cell.cc, ov-cell.h,
ov-ch-mat.cc, ov-class.cc, ov-class.h, ov-classdef.cc,
ov-fcn-handle.cc, ov-java.cc, ov-lazy-idx.h, ov-perm.cc, ov-perm.h,
ov-range.h, ov-str-mat.cc, ov-struct.cc, ov-struct.h, ov-usr-fcn.cc,
ov-usr-fcn.h, ov.cc, ov.h, ovl.cc, octave.cc, bp-table.cc, jit-ir.cc,
jit-ir.h, jit-typeinfo.cc, jit-typeinfo.h, jit-util.h, lex.h, lex.ll,
oct-lvalue.cc, oct-parse.yy, parse.h, profiler.h, pt-eval.cc,
pt-eval.h, pt-jit.cc, pt-jit.h, pt-pr-code.cc, pt-tm-const.cc,
pt-tm-const.h, Array.h, CMatrix.cc, DiagArray2.h, PermMatrix.h,
Sparse.h, dMatrix.cc, fCMatrix.cc, fMatrix.cc, bsxfun-defs.cc,
oct-fftw.cc, oct-fftw.h, randpoisson.cc, sparse-chol.cc,
mx-inlines.cc, file-ops.cc, lo-sysdep.cc, oct-env.cc, oct-time.cc,
action-container.cc, action-container.h, base-list.h, caseless-str.h,
cmd-edit.cc, cmd-hist.cc, data-conv.cc, data-conv.h, f77-fcn.h,
file-info.cc, file-info.h, kpse.cc, kpse.h, lo-cutils.h, lo-hash.h,
lo-regexp.cc, oct-base64.cc, oct-base64.h, oct-binmap.h, oct-glob.cc,
oct-shlib.cc, oct-shlib.h, oct-sort.cc, oct-sparse.h, oct-string.cc,
quit.cc, unwind-prot.h, url-transfer.cc, main.in.cc, mkoctfile.in.cc,
and shared-fcns.h.
(grafted from aef11bb4e6d1f303ad9de5688fcb7244ef48867e)
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Wed, 28 Apr 2021 22:57:42 -0400 |
parents | 0a5b15007766 |
children | 7854d5752dd2 |
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//////////////////////////////////////////////////////////////////////// // // Copyright (C) 1996-2021 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/>. // //////////////////////////////////////////////////////////////////////// // Originally written by A. S. Hodel <scotte@eng.auburn.edu> #if defined (HAVE_CONFIG_H) # include "config.h" #endif #include "defun.h" #include "error.h" #include "ovl.h" DEFUN (givens, args, nargout, doc: /* -*- texinfo -*- @deftypefn {} {@var{G} =} givens (@var{x}, @var{y}) @deftypefnx {} {[@var{c}, @var{s}] =} givens (@var{x}, @var{y}) Compute the Givens rotation matrix @var{G}. @tex The Givens matrix is a $2\times 2$ orthogonal matrix $$ G = \left[\matrix{c & s\cr -s'& c\cr}\right] $$ such that $$ G \left[\matrix{x\cr y}\right] = \left[\matrix{\ast\cr 0}\right] $$ with $x$ and $y$ scalars. @end tex @ifnottex The Givens matrix is a 2-by-2 orthogonal matrix @example @group @var{G} = [ @var{c} , @var{s} -@var{s}', @var{c}] @end group @end example @noindent such that @example @var{G} * [@var{x}; @var{y}] = [*; 0] @end example @noindent with @var{x} and @var{y} scalars. @end ifnottex If two output arguments are requested, return the factors @var{c} and @var{s} rather than the Givens rotation matrix. For example: @example @group givens (1, 1) @result{} 0.70711 0.70711 -0.70711 0.70711 @end group @end example Note: The Givens matrix represents a counterclockwise rotation of a 2-D plane and can be used to introduce zeros into a matrix prior to complete factorization. @seealso{planerot, qr} @end deftypefn */) { if (args.length () != 2) print_usage (); octave_value_list retval; if (args(0).is_single_type () || args(1).is_single_type ()) { if (args(0).iscomplex () || args(1).iscomplex ()) { FloatComplex cx = args(0).float_complex_value (); FloatComplex cy = args(1).float_complex_value (); FloatComplexMatrix result = Givens (cx, cy); switch (nargout) { case 0: case 1: retval = ovl (result); break; case 2: retval = ovl (result(0, 0), result(0, 1)); break; } } else { float x = args(0).float_value (); float y = args(1).float_value (); FloatMatrix result = Givens (x, y); switch (nargout) { case 0: case 1: retval = ovl (result); break; case 2: retval = ovl (result(0, 0), result(0, 1)); break; } } } else { if (args(0).iscomplex () || args(1).iscomplex ()) { Complex cx = args(0).complex_value (); Complex cy = args(1).complex_value (); ComplexMatrix result = Givens (cx, cy); switch (nargout) { case 0: case 1: retval = ovl (result); break; case 2: retval = ovl (result(0, 0), result(0, 1)); break; } } else { double x = args(0).double_value (); double y = args(1).double_value (); Matrix result = Givens (x, y); switch (nargout) { case 0: case 1: retval = ovl (result); break; case 2: retval = ovl (result(0, 0), result(0, 1)); break; } } } return retval; } /* %!assert (givens (1,1), [1, 1; -1, 1] / sqrt (2), 2*eps) %!assert (givens (1,0), eye (2)) %!assert (givens (0,1), [0, 1; -1 0]) %!error givens () %!error givens (1) %!error [a,b,c] = givens (1, 1) */