It can be difficult to know what an iterable is, and if you’re reading this article, you might not know yet. An iterable is a type of sequence that we can loop through using for loops in Python. You can also use the built-in function iter() to create an iterator object from any data structure with a __getitem__ method. This means that some objects can only be accessed sequentially; they are not designed for random access or modification by indexing like arrays.
The following are all iterables:
a list, tuple, or other sequence (e.g., string) of values can be obtained by accessing successive members with the built-in function ‘next()’
an object implementing __iter__ to return self in iterator form
and some objects that provide it as a method such as dict, file, str.
a generator that produces items on demand
or an iterable that can be traversed by indexing or slicing like arrays (e.g., “range(n)” where n is any number)
Some operations and functions are only available for sequences supporting random access; those operations will raise TypeError if used with non-sequence objects. One example of this type of sequence is the string class which supports searching from either end using ‘find()’ to search in reverse order use ‘rfind()’. Another difference between lists/tuples and strings is the ability to concatenate two list/tuples together into one: >>> my_list = [0] * 1000000 >>> my_tuple = (0,) * 1000000 >>> my_list + my_tuple
[0, 0, 0, …]
However if you try to concatenate a list and string together: >>> ‘abc’ + [‘def’] TypeError: can only join an iterable with another sequence-like object. The first argument must be of type “string” or “bytes”, not “list”. You cannot run this cell as it is now…
How to Join an Iterable: operations will raise TypeError if used with non-sequence objects. One example of this type of sequence is the string class which supports searching from either end using ‘find()’ to search in reverse order use ‘rfind()’. Another difference between lists/tuples and strings is the ability to concatenate two list/tuples together into one: >>> my_list = [0] * 1000000 >>> my_tuple = (0,) * 1000000 >>> my_list + my_tuple
[0, 0, 0, …]
.. can only join an iterable with another sequence-like object. The first argument must be of type “string” or “bytes”, not “list”. You cannot run this cell as it is now…
How to Write in a Language You Don’t Know: There are two ways to declare what language you want the text editor working with. The first way is by using an attribute on the script tag, which can be called type=”text/x-languagecode”. The second option is if your add an “xmlns” declaration (<!DOCTYPE html PUBLIC “-//Www.codecademy.com//DTD HTML+XML V0.92 Polish//EN”, xmlns=”urn:schemas-microsoft-com:office:word” />) at the top of your document (before any content).
The first way is by using an attribute on the script tag, which can be called type=”text/x-languagecode”. The second option is if your add an “xmlns” declaration (<!DOCTYPE html PUBLIC “-//Www.codecademy.com//DTD HTML+XML V0.92 Polish//EN”, xmlns=”urn:schemas-microsoft-com:office:word” />) at the top of your document (before any content).
As a result, you can change these settings in Tools and Options from Languages to Language preferences for this session only but if you use the R code below it will work every time without having to change anything manually on each new editing window opened.:
