All,
Is everyone aware of Coursera.org?
It has online courses for almost everything. Catch up on linear algebra, statistics, machine learning—including deep learning (which I am taking now).
There is an “audit” option that is about as small as it could be. But click it and you can get a degree without the piece of paper and more importantly no fee.
Sorry, they will not let you take a test and have it graded if you click the audit button—I am devastated.
In truth, many of the courses are pretty light (lower division undergraduate) and the test would not help you learn anyway.
Recommended: anything on Gradient Descent (used or could be used with any machine learning tool you mention). You can even do linear regression with Gradient Descent but is a necessary for neural nets for example.
Regards,
-Jim