Set compatibility mode which will affect the way calculations are done by all the extension functions.
</para>
</refsect1>
<refsect1role="parameters">
&reftitle.parameters;
<variablelist>
<varlistentry>
<term><parameter>compatId</parameter></term>
<listitem>
<para>
Compatibility Id. <linkxmlns="http://docbook.org/ns/docbook"linkend="trader.constants">TRADER_COMPATIBILITY_*</link> series of constants should be used.