radio button

i created radio button.but I want to update records suppose at the time of creation i selected present but when i want to update record that time that radio button not showing selected plllzzz anybody help me

here is my update code i m creating add more radio buttons

<table id="mytbl">

    &lt;tr&gt;





       &lt;td&gt;Subject&lt;/td&gt;


       &lt;td&gt;Marks&lt;/td&gt;


       &lt;td&gt;Attendance&lt;/td&gt;


       


    &lt;/tr&gt;


    


    &lt;?php  if(empty(&#036;_GET['id'])){?&gt;


   


     &lt;tr class=&quot;mainrow&quot;&gt;


    &lt;td&gt;&lt;?php echo &#036;form-&gt;textField(&#036;Studmarks,'Subject[]',array('size'=&gt;20,'maxlength'=&gt;11)); ?&gt;&lt;/td&gt;


    &lt;td&gt;&lt;?php echo &#036;form-&gt;textField(&#036;Studmarks,'Marks[]',array('size'=&gt;20,'maxlength'=&gt;11)); ?&gt;&lt;/td&gt;

<!-- <td><?php //echo $form->checkBoxList($Studmarks,‘language[0]’,array(‘java’ => ‘Java’,‘C++’ => ‘C++’)); ?></td>

    --&#62; 


   &lt;td&gt;&lt;?php echo &#036;form-&gt;radioButtonList(&#036;Studmarks,'attendance[0]',array('present'=&gt;'present','absent'=&gt;'absent'));?&gt;&lt;/td&gt;


   &lt;td&gt;&lt;button type=&quot;button&quot; name=&quot;add&quot; id=&quot;add&quot;&gt;Add more&lt;/button&gt; &lt;/td&gt;


   &lt;/tr&gt;


   


   &lt;?php }


    else 


    { 


     &#036;arr_len = count(&#036;Studmarks);


     &#036;a=1;


     for(&#036;i=0;&#036;i&lt;&#036;arr_len;&#036;i++)


     { 


  ?&gt;


   &lt;tr&gt;


   &lt;td&gt;


   &lt;input type='hidden' name='StudMarks[Mid][]' id='MarksData_marks_id' value=&quot;&lt;?php echo &#036;Studmarks[&#036;i]['Mid'];?&gt;&quot;&gt;   


   &lt;input size=&quot;20&quot; maxlength=&quot;11&quot; name=&quot;StudMarks[&lt;?php echo &#036;i;?&gt;]&quot; id=&quot;StudMarks_Subject&quot; type=&quot;text&quot; value=&quot;&lt;?php echo &#036;Studmarks[&#036;i]['Subject'];?&gt;&quot;&gt;&lt;/td&gt;   


   &lt;td&gt;&lt;input size=&quot;20&quot; maxlength=&quot;11&quot; name=&quot;StudMarks[&lt;?php echo &#036;i;?&gt;]&quot; id=&quot;StudMarks_Marks&quot; type=&quot;text&quot; value=&quot;&lt;?php echo &#036;Studmarks[&#036;i]['Marks'];?&gt;&quot;&gt;&lt;/td&gt;


   


   &lt;td&gt;&lt;input size=&quot;20&quot; maxlength=&quot;11&quot; name=&quot;StudMarks[&lt;?php echo &#036;i;?&gt;]&quot; id=&quot;StudMarks_attendance&quot; type=&quot;radiobutton&quot; value=&quot;&lt;?php echo &#036;Studmarks[&#036;i]['attendance'];?&gt;&quot; uncheckValue=&quot;null&quot;&gt;&lt;/td&gt;


    &lt;td&gt;&lt;input size=&quot;20&quot; maxlength=&quot;11&quot; name=&quot;StudMarks[&lt;?php echo &#036;i;?&gt;]&quot; id=&quot;StudMarks_attendance1&quot; type=&quot;radiobutton&quot; value=&quot;&lt;?php echo &#036;Studmarks[&#036;i]['attendance'];?&gt;&quot; uncheckValue=&quot;null&quot;&gt;&lt;/td&gt;





   &lt;?php if(&#036;a==1){?&gt;


   &lt;td&gt;&lt;button type=&quot;button&quot; name=&quot;add&quot; id=&quot;add&quot;&gt;Add more&lt;/button&gt;


   &lt;?php &#036;a++;


   }?&gt;


   &lt;/tr&gt;





   &lt;?php }                    


   }?&gt;


    &lt;/table&gt;