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<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" xmlns:scilab="http://www.scilab.org" xml:lang="ja" xml:id="givens">

    <refnamediv>

        <refname>givens</refname>

        <refpurpose>ギブンス変換</refpurpose>

    </refnamediv>

    <refsynopsisdiv>

        <title>呼び出し手順</title>

        <synopsis>U=givens(xy)

            U=givens(x,y)

            [U,c]=givens(xy)

            [U,c]=givens(x,y)

        </synopsis>

    </refsynopsisdiv>

    <refsection>

        <title>引数</title>

        <variablelist>

            <varlistentry>

                <term>x,y</term>

                <listitem>

                    <para>実数または複素数</para>

                </listitem>

            </varlistentry>

            <varlistentry>

                <term>xy</term>

                <listitem>

                    <para>実数または複素数の要素数2の列ベクトル</para>

                </listitem>

            </varlistentry>

            <varlistentry>

                <term>U</term>

                <listitem>

                    <para>2x2 ユニタリ行列</para>

                </listitem>

            </varlistentry>

            <varlistentry>

                <term>c</term>

                <listitem>

                    <para>実数または複素数の要素数2の列ベクトル</para>

                </listitem>

            </varlistentry>

        </variablelist>

    </refsection>

    <refsection>

        <title>説明</title><literal>xy = [x;y]</literal>として

        <para>

            <literal>U= givens(x, y)</literal> または <literal>U = givens(xy)</literal>

            は,次のような<literal>2</literal>x<literal>2</literal> の

            ユニタリ行列 <literal>U</literal> を返します:

        </para>

        <para>

            <literal>U*xy=[r;0]=c</literal>.

        </para>

        <para>

            <note>

                <literal>givens(x,y)</literal> および <literal>givens([x;y])</literal> は等価であることに

                注意してください.

            </note>

        </para>

    </refsection>

    <refsection>

        <title>例</title>

        <programlisting role="example"><![CDATA[
A=[3,4;5,6];
U=givens(A(:,1));
U*A
 ]]></programlisting>

    </refsection>

    <refsection role="see also">

        <title>参照</title>

        <simplelist type="inline">

            <member>

                <link linkend="qr">qr</link>

            </member>

        </simplelist>

    </refsection>

</refentry>

