How do I remove the value from a gauge chart?

[Bevan]

I have a gauge chart that uses a locally sourced variable '@conv'.

Here is the code:

<script type='text/javascript'>
      google.load('visualization', '1', {packages:['gauge']});
      google.setOnLoadCallback(drawChart);
      function drawChart() {
        var data = google.visualization.arrayToDataTable([
          ['Label', 'Value'],
          ['', @conv],
        ]);
 
        var options = {
          width: 150, height: 200,
          redFrom: 0, redTo: 0.50,
          yellowFrom:0.50, yellowTo: 0.59,
          minorTicks: 10,
          max: 1, greenFrom:0.60,
          greenTo:1
        };
 
        var chart = new google.visualization.Gauge(document.getElementById('conv_dial'));
        chart.draw(data, options);
      }
    </script>
As you can see, I've taken the Label off by passing an empty value for it: ''. 
The gauge works fine, but it also displays the value in text, right across the bottom of the gauge. As the value is a percentage with 10 decimal places... its really messy.

How do I remove the text from the visualisation? Or format it, even?

Thanks in advance.

[Bevan]

Attached: an image of the current, messy, result.

[asgallant]

Set the formatted value of your data to an empty string:

var data = google.visualization.arrayToDataTable([
     ['Label', 'Value'],

     ['', {v: @conv, f: ''}],
]);

[Bevan]

Perfect. Thanks!

[Bevan]

Is there documentation somewhere about this formatting stuff? I now want to have it format as a dollar figure.

[Andrew Gallant]

The easy way to do that is to use a NumberFormatter:

var formatter = new google.visualization.NumberFormat({pattern: '$#.00'});

// format column 1 of DataTable data

formatter.format(data, 1);

Specifying the formatted value of cells when constructing the DataTable is described in the DataTable JSON structure.  The object specification ({v: value, f: formattedValue}) also happens to work with the arrayToDataTable function, but I do not believe it is documented anywhere.

[zxtonizx]

This also really helped me. Thank you

[Andreas Reitberger]

Is it possible to hide the min and max value in this chart?