Too Long; Didn't Read
PHP has been into market for more than 2 decades and there has been no machine learning with PHP. Now with release of PHP7.2 few options are available to do ML and AI related work. PHP is unusual option for ML, and since its always leaned towards the web application development. PHP could be used to work on small datasets, and PHP could work on data cleanups and feature extractions. RubixML is a high level Machine learning library that offers around 40+ supervised and un-supervised algorithms to solve computer problems.