Actually, I think that principal components is a horrible way of look at programming. Programming is, essentially, the art of instructing a being as to what to do. This being has an IQ of 0, but perfect recall, and will do actions over and over until told to stop. There is no analysis by the being as to what it's told to do.

As for a human reader, the analysis is focused on atoms, which can be viewed as roughly analogous to principal components, but they're not.

The first principal component is meant to convey the most information about the data space/solution space. The next will convey the most of whatever the first couldn't convey, and so on.

In programming, the goal is for each atom (or component) to convey only as much information as is necessary for it to be a meaningful atom. Thus, the programmer builds up larger atoms from smaller atoms. The goal is to eventually reach the 'topmost' structure, which would be the main() function in C, for example. That function is built completely of calls to language syntax and other atoms, whose names should reflect what that syntax or atom is doing. Thus, we don't have if doing what while would do, and vice versa.

In data analysis, you want to look at the smallest number of things that give you the largest amount of knowledge of your dataset. But, you're not analyzing data. You're reading algorithms, which do not compose a dataset in the same way that observed waveforms would. To understand an algorithm, you have to understand its component parts, or atoms.

Think of it this way - when you explain a task to someone else, say a child, you break it down into smaller tasks. You keep doing so until each task is comprehensible by the recipient. At that point, you have transmitted atoms. At no point have you attempted to convey as much information as possible in one task. Each task is of similar complexity, or contains similar amounts of information.

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.