Question

This sorts in one direction, but not the other. Is there something wrong with the table specifications. It wold be great if someone could post an HTML sample that has sorting working in both directions on a column with dollar values that include commas in them.

// create sorter
<script type="text/javascript" id="js">
    $(document).ready(function() {
        // call the tablesorter plugin
        $("table.tablesorter").tablesorter({
            // enable debug mode
            debug: false
        });
    }); 
</script>

Not sure if a prefix is needed here (table.tablesorter):

// add parser through the tablesorter addParser method
<script type="text/javascript" id="js">
$.tablesorter.addParser({
    // set a unique id
    id: 'money',
    is: function(s) {
        // return false so this parser is not auto detected
        return false;
    },
    format: function(s) {
         return s.toLowerCase().replace("\$","").replace(",","");
    },
    // set type, either numeric or text
    type: 'numeric'
});

Not sure if table.tablesorter is needed here:

// specify column  
$(function() {  
    $("table.tablesorter").tablesorter({  
        headers: {  
            // column to be handled specially
            7: {  
                sorter:'money'  
            }  
        }
    });
});                 
</script>

The following is the top of the table:

<table cellspacing="1" class="tablesorter">  
    <thead>  
        <tr>  
            <th>Name</th>  
            <th>Major</th>  
            <th>Gender</th>  
            <th>English</th>  
            <th>Japanese</th>  
            <th>Calculus</th>  
            <th>Overall grades</th>  
            <th>Money</th>  
        </tr>  
    </thead>  
    <tbody>  
        <tr>  
            <td>Student01</td>  
            <td>Languages</td>  
            <td>male</td>  
            <td>80</td>  
            <td>70</td>  
            <td>75</td>  
            <td>bad</td>  
            <td>$1.00</td>  
        </tr>  

Answer 1

Since you are working with numbers, you’ll need to parse the string into a real number. Change this line in your parser:

format: function(s) {
  return parseFloat( s.toLowerCase().replace("\$","").replace(",","") );
}