 <OpenGeoSysProjectDiff base_file="square_1e2.prj">

   <remove sel=".//parameters/parameter/name[text()="E"]/.." />

   <add sel=".//parameters">

     <parameter>

       <name>E</name>

       <type>Function</type>

       <expression>if (x < 2) 19; else if (x < 2.1) 0.95; else 9.5;</expression>

     </parameter>

   </add>

   <replace sel=".//time_loop/output/prefix/text()">square_1e2_function</replace>

 </OpenGeoSysProjectDiff>