Hello Dave

If you have zeros in your table, that is an issue we've been dealing with, because integer and float columns cannot have anything other than numbers in them, the plugin is treating an empty cell as "0"

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

/wp-content/plugins/wpdatatables/source/class.wpdatachart.php around line 1631:

case 'int':
   $return_data_row[] = (float)$row[$columnKey];
 break;
   case 'float':
     if ($decimalPlaces != -1){
       $return_data_row[] = (float)number_format(
         (float)($row[$columnKey]),
         $decimalPlaces,
         '.',
         $thousandsSeparator ? '' : '.');
       }else {
           $return_data_row[] = (float)$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[$columnKey];
                                }
                                break;
                            case 'float':
                               if ($decimalPlaces != -1) {
                                   if (is_null($row[$columnKey])) {
                                       $return_data_row[] = null;
                                   }else {
                                       $return_data_row[] = (float)number_format(
                                           (float)($row[$columnKey]),
                                           $decimalPlaces,
                                           '.',
                                           $thousandsSeparator ? '' : '.');
                                   }
                               } else {
                                   if (is_null($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).on('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 the page.

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

I hope this helps.

Hello again Dave

Spline charts have smooth lines by default.

In this example, the green is a spline line, and the blue one behind it is a line, so you can see that spline is rather smooth, and line is sharp.

Hello Dave.

Did this callback work for you before? I know I've tested it in the past, and it used to work, but I can't get it to work on my local environment either.

I forwarded the callback to one of our developers, so he can take a look at it, and as soon as I hear from him I will let you know. Please note, though, that using callbacks requires some coding knowledge, and included support refers only to advice, so I can't guarantee anything.

I'm pretty confident that we'll be able to get to the bottom of this, as this is a simple placeholder, and it used to work. As soon as I hear from our developer, I will let you know.

Hi again Dave

I need to watch out for terminology in the future

Your initial comment on this ticket was this:

Can you advise on how to plot empty values so that they are not rendered in the chart?

So, I assumed you were referring to NULL values, not zeros, even though you commented that they are saved as zeros right below that. Sorry about the misunderstanding. Empty (NULL) values, are different from zeros ( 0 ), and the code that I sent you works when the data in the columns is saved as NULL in the database. Since you have them saved as zeros, this code won't work.

To use this callback for tables with zeros, you need to change the code in file /wp-content/plugins/wpdatatables/source/class.wpdatachart.php around line 1631 from:

case 'int':
   $return_data_row[] = (float)$row[$columnKey];
 break;
   case 'float':
     if ($decimalPlaces != -1){
       $return_data_row[] = (float)number_format(
         (float)($row[$columnKey]),
         $decimalPlaces,
         '.',
         $thousandsSeparator ? '' : '.');
       }else {
           $return_data_row[] = (float)$row[$columnKey];
       }
break;

To this:

case 'int':
                                if ($row[$columnKey] == 0) {
                                    $return_data_row[]= null;
                                }else{
                                    $return_data_row[] = (float)$row[$columnKey];
                                }
                                break;
                            case 'float':
                               if ($decimalPlaces != -1) {
                                   if ($row[$columnKey] == 0) {
                                       $return_data_row[] = null;
                                   }else {
                                       $return_data_row[] = (float)number_format(
                                           (float)($row[$columnKey]),
                                           $decimalPlaces,
                                           '.',
                                           $thousandsSeparator ? '' : '.');
                                   }
                               } else {
                                   if ($row[$columnKey] == 0) {
                                       $return_data_row[] = null;
                                   }else {
                                       $return_data_row[] = (float)$row[$columnKey];
                                   }
                               }
                                break;

The difference between this, and what I previously sent is this:

This is used when data in the database (in your table) is saved with empty values (NULL):

if (is_null($row[$columnKey])){

And the code that I just posted above is used when the data is saved with zeros:

if ($row[$columnKey] == 0) {

When you apply the code above, and use the same callback I provided in my initial response, it will work. I just tested it locally, and it works fine.

Great news, Dave

Thank you for letting me know.

Can you please show me how the table looks like, what chart you used, and which callback exactly, and I'll add it to our FAQ section (when I have time).

Awesome, Dave, thanks!

Just a screenshot of the table, please, and I'll leave you to your work

Hi, Petr 

If you need a workaround for charts to "skill NULL and 0 values",

Please go to the functions.php file of your theme or child theme, and add this:

function filterNullValues ($value, $origHeader ,$chartID, $tableID){
     // You can add conditions for specific org header, chart id or table id
    // Here we only check if value is null and provide same value to the chart object
    if (is_null($value) || $value == 0){
        $value = null;
    }
    return $value;
}
add_filter( 'wpdatatables_filter_int_cell_data_in_charts', 'filterNullValues', 10, 4 );
add_filter( 'wpdatatables_filter_float_cell_data_in_charts', 'filterNullValues', 10, 4 );
This works for integer and float columns that have NULL values and "0" values.

If you want to apply it just for NULL values, you can use this code:

function filterNullValues ($value, $origHeader ,$chartID, $tableID){
     // You can add conditions for specific org header, chart id or table id
    // Here we only check if value is null and provide same value to the chart object
    if (is_null($value)){
        $value = null;
    }
    return $value;
}
add_filter( 'wpdatatables_filter_int_cell_data_in_charts', 'filterNullValues', 10, 4 );
add_filter( 'wpdatatables_filter_float_cell_data_in_charts', 'filterNullValues', 10, 4 );
And if you want to apply it just for "0" values, you can use this code:
function filterNullValues ($value, $origHeader ,$chartID, $tableID){
     // You can add conditions for specific org header, chart id or table id
    // Here we only check if value is null and provide same value to the chart object
    if ($value == 0){
        $value = null;
    }
    return $value;
}
add_filter( 'wpdatatables_filter_int_cell_data_in_charts', 'filterNullValues', 10, 4 );
add_filter( 'wpdatatables_filter_float_cell_data_in_charts', 'filterNullValues', 10, 4 );

You don't need to change the code after the plugin updates, but you will need to keep this code in functions.php.

If you want to connect data with NULLs skipped, you can use this callback: https://jsfiddle.net/gh/get/library/pure/highcharts/highcharts/tree/master/samples/highcharts/plotoptions/series-connectnulls-true/

<script type="text/javascript">
jQuery(window).on('load',function(){
    if( typeof wpDataChartsCallbacks == 'undefined' ){ wpDataChartsCallbacks = {}; }
    wpDataChartsCallbacks[16] = function(obj){
        obj.options.plotOptions = {
            series: {
                connectNulls: true
            }
        }
    };
});
</script>

Just make sure to replace [16] with the ID of your chart.

Let us know if that works for your use-case. Thanks

Hi, Petr.

Could you please open a new ticket from your account,

then we can ask you for WP-Admin remote access, if thats'OK,  so we can inspect how you added this on your site and why it is not working.

When we try the same method, it is working to "skip NULL /blank" values on our charts on all our testing sites,

and so far for all other users that requested it,  it also works for them.

So, it might be due to something with the Shortcoder plugin, but not sure.

Did you try to add the said function directly in your functions.php file of the Theme?

In either case, we can certainly check this out remotely and try to debut the issue on your site - but if you can make a new ticket, so that we can privately exchange the access URL + Admin credentials in Private messages, for safety reasons.

Thank you.