Hello,
Yes, it's the same link, we pointed out the groupBar parameter and the API addChart page (both are the same page). You can set groupBar as clustered and in the data array you set the values of the array; the included sample addChart/sample_3.php uses the groupBar option.
If you think you may need further support about this task, you could open a support ticket (https://www.phpdocx.com/support) an a member of the dev team will create a custom script.
Regards.