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 * Copyright (C) INRIA - Jean-Baptiste Silvy
 * Copyright (C) 2013, 2017 - Samuel GOUGEON
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<refentry xml:lang="en" xml:id="clf">
    <refnamediv>
        <refname>clf</refname>
        <refpurpose>
            Clears and resets a figure or a frame uicontrol
        </refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>Syntax</title>
        <synopsis>
            clf
            clf reset
            clf(numFig)
            clf(numFig, "reset")
            clf(figFrameHandle)
            clf(figFrameHandle, "reset")
        </synopsis>
    </refsynopsisdiv>
    <refsection>
        <title>Arguments</title>
        <variablelist>
            <varlistentry>
                <term>numFig</term>
                <listitem>
                    <para>
                        Vector of indices of figures to clear or reset (<literal>.figure_id</literal>
                        values). By default, the current figure is targeted.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>figFrameHandle</term>
                <listitem>
                    <para>
                        Vector of handles of figures or frame uicontrol to clear or reset. Mixing
                        figures and frames is possible. By default, the current figure is targeted.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>"reset"</term>
                <listitem>
                    Provide this option keyword to reset properties of chosen figures to their
                    default values, in addition to deleting the figures contents.
                </listitem>
            </varlistentry>
        </variablelist>
    </refsection>
    <refsection>
        <title>Description</title>
        <para>
            The <literal>clf</literal> command can be used to delete all children of a given
            graphic window, hence clearing it. If the <literal>"reset"</literal> keyword is used,
            in addition most of the figure properties are reset to their default values.
            The detailled changes are now described:
        </para>
        <para>
            <orderedlist>
                <listitem>
                     The following default actions are always performed:
                    <para>
                    <itemizedlist>
                        <listitem>
                            All visible and invisible axes of each targeted figure or frame are
                            deleted.
                        </listitem>
                        <listitem>
                            All menus whose figure.children handles are not hidden are deleted.
                            It is possible to protect them with
                            <literal>set(get(0), "ShowHiddenHandles", "off")</literal>.
                            This then applies to all opened figures and forthcoming ones.
                            See <link linkend="console_properties">ShowHiddenHandles</link>.
                        </listitem>
                        <listitem>
                            The message in the status bar of each figure is cleared.
                        </listitem>
                        <listitem>
                            The event handler of each figure is disabled, but their references are kept .
                        </listitem>
                    </itemizedlist>
                    </para>
                    <para>
                        Values of all <link linkend="figure_properties">figures properties</link>
                        are unchanged, except <literal>.info_message=""</literal> and
                        <literal>.event_handler_enable="off"</literal> that are forced.
                    </para>
                </listitem>
                <listitem>
                    <para>
                        <literal>"reset"</literal>: in addition to default actions,
                        <literal>"reset"</literal> resets most of figures properties to their
                        default values, as specified by <function>gdf()</function>.
                        This applies only to figures.
                    </para>
                    <warning>
                        <itemizedlist>
                            <listitem>
                                <emphasis role="italic">Some properties are never reset</emphasis>:
                                The figure's number <literal>.figure_id</literal> is kept as is.
                                <literal>.toolbar</literal>,  <literal>.menubar</literal>,
                                <literal>.layout</literal>,  <literal>.layout_options</literal>,
                                and <literal>.dockable</literal> can be set only once and so are
                                never resettable.
                            </listitem>
                            <listitem>
                                <emphasis role="italic">For docked figures</emphasis>:
                                <literal>.figure_position</literal>, <literal>.figure_size</literal>,
                                and <literal>.axes_size</literal> are unchanged if the parent figure
                                is docked to the Scilab's desktop or to another Scilab interface.
                                Changing their value would change the position or size of the whole
                                block of docked interfaces, not only the targeted figure.
                            </listitem>
                        </itemizedlist>
                    </warning>
                </listitem>
            </orderedlist>
        </para>
        <refsect2>
            <title>Clearing specific parts of a figure</title>
            <itemizedlist>
                <listitem>
                    <literal>gcf().name = ""</literal> clears the
                    name of the window, displayed at its very top left corner.
                </listitem>
                <listitem>
                    <literal>gcf().info_message = ""</literal>
                    clears the message displayed in the status bar of the current figure.
                </listitem>
                <listitem>
                    <literal>delete(gca())</literal> deletes the current axes in the current window.
                    All other components of the window are kept: other axes (if any), menus,
                    interactive components, figure properties, etc.
                </listitem>
                <listitem>
                    Deleting only all axes of a figure may be done with
                    <literal>c=gcf().children; delete(c(c.type=="Axes"))</literal>. This keeps all
                    its other components: menus, interactive components, etc.
                </listitem>
                <listitem>
                    Deleting only menus: <literal>c=gcf().children; delete(c(c.type=="uimenu"))</literal>.
                    This assumes that <literal>get(0).ShowHiddenHandles</literal> is
                    <literal>"on"</literal>.
                </listitem>
            </itemizedlist>
        </refsect2>
    </refsection>
    <refsection>
        <title>Examples</title>
        <programlisting role="example">
            f4 = scf(4);  //creates figure with id==4 and makes it the current one
            f4.color_map = jetcolormap(64);
            f4.figure_size = [400, 200];
            plot2d()
            sleep(4000)   // wait and see for 4s
            clf(f4, "reset")

            f0 = scf(0); //creates figure with id==0 and make it the current one
            f0.color_map = hotcolormap(128); // changes color map
            t = -%pi:0.3:%pi;
            plot3d1(t,t,sin(t)'*cos(t));

            clf        // is clf(gcf(),"clear"). Keeps the current color_map
            plot3d1(t,t,sin(t)'*cos(t));

            clf reset  // resets the color_map to the default one with 32 colors
            plot3d1(t,t,sin(t)'*cos(t));

            fr = uicontrol("Style", "frame", "Position", [20 20 200 200]);
            a = newaxes(fr);
            plot(1:10);
            clf(fr);
        </programlisting>
    </refsection>
    <refsection role="see also">
        <title>See also</title>
        <simplelist type="inline">
            <member>
                <link linkend="figure_properties">figure properties</link>
            </member>
            <member>
                <link linkend="console_properties">ShowHiddenHandles</link>
            </member>
            <member>
                <link linkend="uicontrol">frames</link>
            </member>
            <member>
                <link linkend="uimenu">menus</link>
            </member>
            <member>
                <link linkend="gcf">gcf</link>
            </member>
            <member>
                <link linkend="gdf">gdf</link>
            </member>
            <member>
                <link linkend="colordef">colordef</link>
            </member>
            <member>
                <link linkend="delete">delete</link>
            </member>
            <member>
                <link linkend="close">close</link>
            </member>
            <member>
                <link linkend="clc">clc</link>
            </member>
            <member>
                <link linkend="clear">clear</link>
            </member>
        </simplelist>
    </refsection>
    <refsection>
        <title>History</title>
        <revhistory>
            <revision>
                <revnumber>5.5.0</revnumber>
                <revremark>
                    <literal>clf</literal> now clears frames as well.
                </revremark>
            </revision>
            <revision>
                <revnumber>6.0.0</revnumber>
                <revremark>
                    <literal>clf('reset')</literal> no longer resizes nor moves docked figures.
                </revremark>
            </revision>
        </revhistory>
    </refsection>
</refentry>
