how to submit radio button value using php code example

Example 1: radio button select in php

<?php echo ($signi== 'Yes') ?  "checked" : "" ;  ?>

Example 2: php code to submit a radio button value using onclick function

Foo: 
<input type='radio' name='foo' value='bar'> Bar <br>
<input type='radio' name='foo' value='fru'> Fru