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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="en" xml:id="csgn">
    <refnamediv>
        <refname>csgn</refname>
        <refpurpose>returns the sign of a vector of real of complex values </refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>Syntax</title>
        <synopsis>s = csgn(z)</synopsis>
    </refsynopsisdiv>
    <refsection>
        <title>Arguments</title>
        <variablelist>
            <varlistentry>
                <term>z</term>
                <listitem>
                    <para>
                        a vector of values on which we want to compute the sign
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>s</term>
                <listitem>
                    <para>if the real part is not equal to zero:</para>
                    <itemizedlist>
                        <listitem>
                            <para>
                                <literal>+1</literal> if the real part of an element is positive
                            </para>
                        </listitem>
                        <listitem>
                            <para>
                                <literal>-1</literal> if the real part of an element is negative
                            </para>
                        </listitem>
                    </itemizedlist>
                    <para>If the real part is equal to zero:</para>
                    <itemizedlist>
                        <listitem>
                            <para>
                                <literal>+1</literal> if the imaginary part of an element is positive
                            </para>
                        </listitem>
                        <listitem>
                            <para>
                                <literal>-1</literal> if the imaginary part of an element is negative
                            </para>
                        </listitem>
                    </itemizedlist>
                    <para>
                        if the element is equal to zero, then returns <constant>%nan</constant>
                    </para>
                </listitem>
            </varlistentry>
        </variablelist>
    </refsection>
    <refsection>
        <title>Description</title>
        <para>
            The <function>csgn</function> function returns the sign of a vector of real of complex values <varname>z</varname>.
        </para>
    </refsection>
    <refsection>
        <title>Examples</title>
        <programlisting role="example"><![CDATA[
A = [1 1+%i 0 -1 1-%i -1-%i];
csgn(A)
 ]]></programlisting>
    </refsection>
    <refsection role="see also">
        <title>See also</title>
        <simplelist type="inline">
            <member>
                <link linkend="sign">sign</link>
            </member>
            <member>
                <link linkend="signm">signm</link>
            </member>
        </simplelist>
    </refsection>
</refentry>
