Hello andres

Thank you for your purchase.

I am sorry to disappoint you, but unfortunately something like this is not possible with the plugin's built-in features.

Integer and float columns cannot have anything other than numbers in them, the plugin is treating an empty cell as "0"

I can try to help you out, but you have to make some changes in code in file :

/wp-content/plugins/wpdatatables/source/class.wpdatachart.php around line 1629:

case 'int':
    $return_data_row[] = (float)$row[$columnKey];
    break;
case 'float':
    $return_data_row[] = (float)$row[$columnKey];
    break;

and replace it with this

case 'int':
    if (is_null($row[$columnKey])){
        $return_data_row[]=null;
    }else{
       $return_data_row[] = (float)$row[$columnKey];
    }
    break;
case 'float':
    if (is_null($row[$columnKey])){
         $return_data_row[]=null;
    }else{
         $return_data_row[] = (float)$row[$columnKey];
    }
    break;                            

With these changes you will get charts like on the first screenshot below.

If you want to make charts like on screenshot #2 you have to use wpdatachart callbacks and insert that on page where your chart is.

<script type="text/javascript">
jQuery(window).load(function(){
    if( typeof wpDataChartsCallbacks == 'undefined' ){ wpDataChartsCallbacks = {}; }
        wpDataChartsCallbacks[39] = function(obj){
                obj.options.plotOptions.series= {connectNulls: true};
            }
});
</script>

One more thing you have to change in this callback number 39 in (wpDataChartsCallbacks[39]) to id of the chart that you use on page.

This will be overwritten on next update so you have to come back here and do it again.

I hope this helps.

If you do need to use wpDataCharts callbacks, I can't help you much with those.

• Every chart exposes several options that customize its look and feel. Charts usually support custom options appropriate to that visualization. wpDataChart callbacks allow adding options that are available in Google Charts API, Highcharts API and Chart.js API. 

• All necessary resources are available in charts engines API (depends on which one you use). Every engine has a different approach to chart settings. In wpDataChart callbacks you have to adopt those settings to the wpDataChart object (you can take a look at examples for each engine in our documentation, and also in Support help center). Huge number of examples for any area of programming can be found on stackoverflow.com (typing your problem in google and at the end add "site: stackoverflow.com" and google will search only that website). Also, a lot of examples of charts, chart settings and customization can be found on jsffidle.net (typing in google for example "line chart highcharts jsffidle")
• Please note that using hooks or wpdatatable and wpDataChart callbacks requires certain level of programming skills and included support refers only to advice.