Save results of Optimize Parameter operator using macros

Hi everybody ,

I want to save result of each combination of parameter values in separate files , I know I have to use macros , but I don't know how to use it here ,

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<process version="5.2.008">
  <context>
    <input/>
    <output/>
    <macros/>
  </context>
  <operator activated="true" class="process" compatibility="5.2.008" expanded="true" name="Process">
    <process expanded="true" height="494" width="1016">
      <operator activated="true" class="generate_massive_data" compatibility="5.2.008" expanded="true" height="60" name="Generate Massive Data" width="90" x="112" y="75">
        <parameter key="number_examples" value="1000"/>
        <parameter key="number_attributes" value="100"/>
        <parameter key="sparse_fraction" value="0.95"/>
      </operator>
      <operator activated="true" class="nominal_to_binominal" compatibility="5.2.008" expanded="true" height="94" name="Nominal to Binominal" width="90" x="313" y="75">
        <parameter key="attribute_filter_type" value="single"/>
        <parameter key="attribute" value="label"/>
        <parameter key="include_special_attributes" value="true"/>
      </operator>
      <operator activated="true" class="optimize_parameters_grid" compatibility="5.2.008" expanded="true" height="94" name="Optimize Parameters (Grid)" width="90" x="514" y="75">
        <list key="parameters">
          <parameter key="Select by Weights.k" value="[10;40;5;linear]"/>
          <parameter key="W-ReliefFAttributeEval.K" value="[5;45;10;linear]"/>
        </list>
        <process expanded="true" height="649" width="1094">
          <operator activated="true" class="weka:W-ReliefFAttributeEval" compatibility="5.1.001" expanded="true" height="76" name="W-ReliefFAttributeEval" width="90" x="179" y="30">
            <parameter key="sort_direction" value="descending"/>
            <parameter key="K" value="45.0"/>
          </operator>
          <operator activated="true" class="select_by_weights" compatibility="5.2.008" expanded="true" height="94" name="Select by Weights" width="90" x="380" y="30">
            <parameter key="weight_relation" value="top k"/>
            <parameter key="weight" value="0.0"/>
            <parameter key="k" value="40"/>
          </operator>
          <operator activated="true" class="x_validation" compatibility="5.2.008" expanded="true" height="112" name="Validation" width="90" x="514" y="30">
            <process expanded="true" height="649" width="522">
              <operator activated="true" class="naive_bayes" compatibility="5.2.008" expanded="true" height="76" name="Naive Bayes" width="90" x="216" y="30"/>
              <connect from_port="training" to_op="Naive Bayes" to_port="training set"/>
              <connect from_op="Naive Bayes" from_port="model" to_port="model"/>
              <portSpacing port="source_training" spacing="0"/>
              <portSpacing port="sink_model" spacing="0"/>
              <portSpacing port="sink_through 1" spacing="0"/>
            </process>
            <process expanded="true" height="649" width="522">
              <operator activated="true" class="apply_model" compatibility="5.2.008" expanded="true" height="76" name="Apply Model" width="90" x="45" y="30">
                <list key="application_parameters"/>
              </operator>
              <operator activated="true" class="performance_binominal_classification" compatibility="5.2.008" expanded="true" height="76" name="Performance" width="90" x="283" y="30">
                <parameter key="accuracy" value="false"/>
                <parameter key="AUC" value="true"/>
                <parameter key="f_measure" value="true"/>
                <parameter key="false_positive" value="true"/>
                <parameter key="false_negative" value="true"/>
                <parameter key="true_positive" value="true"/>
                <parameter key="true_negative" value="true"/>
              </operator>
              <connect from_port="model" to_op="Apply Model" to_port="model"/>
              <connect from_port="test set" to_op="Apply Model" to_port="unlabelled data"/>
              <connect from_op="Apply Model" from_port="labelled data" to_op="Performance" to_port="labelled data"/>
              <connect from_op="Performance" from_port="performance" to_port="averagable 1"/>
              <portSpacing port="source_model" spacing="0"/>
              <portSpacing port="source_test set" spacing="0"/>
              <portSpacing port="source_through 1" spacing="0"/>
              <portSpacing port="sink_averagable 1" spacing="0"/>
              <portSpacing port="sink_averagable 2" spacing="0"/>
            </process>
          </operator>
          <operator activated="true" class="write_as_text" compatibility="5.2.008" expanded="true" height="76" name="Write as Text" width="90" x="782" y="30">
            <parameter key="result_file" value="/home/arian/result%{x1}_%{x2}.res"/>
          </operator>
          <connect from_port="input 1" to_op="W-ReliefFAttributeEval" to_port="example set"/>
          <connect from_op="W-ReliefFAttributeEval" from_port="weights" to_op="Select by Weights" to_port="weights"/>
          <connect from_op="W-ReliefFAttributeEval" from_port="example set" to_op="Select by Weights" to_port="example set input"/>
          <connect from_op="Select by Weights" from_port="example set output" to_op="Validation" to_port="training"/>
          <connect from_op="Validation" from_port="averagable 1" to_op="Write as Text" to_port="input 1"/>
          <connect from_op="Write as Text" from_port="input 1" to_port="performance"/>
          <portSpacing port="source_input 1" spacing="0"/>
          <portSpacing port="source_input 2" spacing="0"/>
          <portSpacing port="sink_performance" spacing="0"/>
          <portSpacing port="sink_result 1" spacing="0"/>
        </process>
      </operator>
      <connect from_op="Generate Massive Data" from_port="output" to_op="Nominal to Binominal" to_port="example set input"/>
      <connect from_op="Nominal to Binominal" from_port="example set output" to_op="Optimize Parameters (Grid)" to_port="input 1"/>
      <portSpacing port="source_input 1" spacing="0"/>
      <portSpacing port="sink_result 1" spacing="0"/>
    </process>
  </operator>
</process>

Thanks ,
Arian