The list x is now the first element of y, followed by the float 3.14 and the complex number -7+4j. Now try y =, and then type y to see what y looks like. ![]() This illustrates that you can mix data types within a list. We can use the same notation to change a list element. The elements of a list are indexed starting with 0 for the first item, so x gives the third element. To access a particular element within a list, give the list’s name followed by the element’s position in square brackets. If you now type x at the prompt, you’ll just get as the response. It’s important to note that ‘ordered’ does not necessarily mean ‘sorted’, so, for example, numeric values in a list need not be in ascending order (although it is possible to sort the items in a list, but that’s a different operation, as we’ll see).īy mutable, we mean that the contents of a list can be changed, either by adding or removing elements, or by changing the data stored at an existing list position.Īs Python is a dynamically typed language, the elements in a list need not all be of the same data type, so we can mix ints, floats, strings and even other lists as elements within a given list.Īt this stage, it’s useful to play around with lists in the PowerShell, so start one up and type ‘python’ at the prompt to enter the Python interpreter.Ī list is specified by typing its elements, separated by commas, between square brackets. It allows duplicate elements, that is, you can have 2 or more elements of the same datum in a list.īy ordered, we mean that the items in a list are stored in a definite order, so that, if we access say the fourth element of the list, it will always be the same datum (unless we’ve modified the list in the meantime). Each of these has its own set of rules and peculiarities.Ī list is an ordered, mutable collection of data elements. ![]() Here we start with some of its basic properties.įirst, it’s important to understand that Python supports four different built-in compound data types: lists, tuples, sets and dictionaries. The Python list is a powerful data type with a lot of functionality, so we’ll cover it in several posts.
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