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Learning Scala online

As I mentioned on my last post I've been attending Functional Programming Principles in Scala course at Coursera. It's been three weeks now and I thought I should express my current feelings about the course.

Course arrangements

Arrangements on the course are just about what I expected. Series of video lectures per week, some quizzes in the videos and homework that's evaluated automatically in a matter of minutes. Homework assignments and videos are given on mondays and homework deadline is in about ten days from that.

On the first three weeks the lectures and homework has been about abstract presentations of entities and mathematical definitions.


Lectures i.e. videos can be viewed online or downloaded and one can also download english subtitles for the videos and the slides shown on videos are also downloadable as pdf's. The subtitles could be helpful sometimes but the quality isn't that good, missing and wrong words, so I don't use them.

The lectures contains theory and basic examples of the weeks topics and mostly I've found them easy to follow.


The videos also contains quizzes in the middle or at the end of the lecture and the quizzes are also resolved in the videos. The quizzes objectives are usually explained so poorly that I don't even try to solve them myself.


The homework... these too are pretty poorly explained and the first thing to do before even trying solve them is to go to the courses forums and read through the assignment FAQ and some of the other posts where people like me don't quite understand what's the objective.

Once I've understood the objective some of the homework has been pretty straight forward but some of them go beyond my understanding and are way more complex than the lecture material presented.

The automatic evaluation process is nice except that sometimes the feedback doesn't help at all. 

Example: This week I got a feedback that filter (this is predefined method that I'm suppose to implement) is too slow and the execution was stopped at 40 seconds. Browsing through the forums I figured out that the problem isn't neccessarily on my filter but on my union (similar predefined method) and got some tips on how to improve my implementation of union. I managed to get my union faster and the evaluation error of my slow filter dissapeared. Too bad I had already lost 3/5 submissions trying to fix my filter.


So far I'm not liking this course. I hate that I'm working on some abstract entities and mathematical definitions. I'm a pragmatic person and I'm just hoping that the course gets more pragmatic or I'll lose my interest. I'm not loosing my interest on Scala just on this course. 

It seems to me that this course is about theory and abstract presentations of what ever more than it's about real life utilisation of functional programming and scala itself.

I'll try to keep myself motivated and hopefully in four or five weeks I can say that I did learn Scala during the course and I've forgotten the unpleasantry of the first three weeks.


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