them, like lists, dictionaries, and files. The built-in types define iterator methods, too. 7 Prefer these methods to methods that return lists, except that you should not mutate a container while iterating having to define lots of functions for the rare exceptions. Also, Python does not support overloaded methods/functions and default arguments are an easy way of “faking” the overloading behavior. Cons: Default accessing or setting data where you would normally have used simple, lightweight accessor or setter methods. Definition: A way to wrap method calls for getting and setting an attribute as a standard attribute

Prefer grouping functions with a namespace instead of using a class as if it were a namespace. Static methods of a class should generally be closely related to instances of the class or the class’s static data erwise, consider a factory function or Init() method. Avoid Init() methods on objects with no other states that affect which public methods may be called (semi-constructed objects of this form are particularly accessing/setting of fields is done by directly accessing the fields rather than through method invocations. Methods should not provide behavior but should only be used to set up the data members, e.g., constructor

avoid using it 2. Functions: errors should be raised using stop() 3. Objects and Methods: avoid S4 objects and methods when possible; never mix S3 and S4 1 Notation and Naming File Names File names stop(). Objects and Methods The S language has two object systems, S3 and S4, both of which are available in R. S3 methods are more interactive and flexible, whereas S4 methods are more formal and rigorous https://cran.r-project.org/doc/Rnews/Rnews_2004-1.pdf.) Use S3 objects and methods unless there is a strong reason to use S4 objects or methods. A primary justification for an S4 object would be to use objects

its members in some logical order, which its maintainer could explain if asked. For example, new methods are not just habitually added to the end of the class, as that would yield “chronological by date logical ordering. 3.4.2.1 Overloads: never split When a class has multiple constructors, or multiple methods with the same name, these appear sequentially, with no intervening members (not even private ones) line appears: 1. Between consecutive members (or initializers) of a class: fields, construc- tors, methods, nested classes, static initializers, instance initializers. 7 • Exception: A blank line between

experiments show that on a few data sets, the results are slightly better than the most naïve prior methods. 13 706.015 Introduction to Scientific Writing – 02 Scientific Reading and Writing Matthias Boehm