Python Data Types For Beginners
Learn how Python variables and data types are similar to and different from other programming languages, and some of Python's built-in data types.
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Python is one of the most preferred programming languages these days. It allows developers to focus all their efforts on implementation instead of complex programs. It provides better readability and ease of access. To master and better use any programming language, you need to develop a thorough understanding of its fundamental concepts. For Python, these concepts are variables and data types.
How are Python Variables and Data Types Different?
If you have been using programming languages like C, C++, and Java, and you think that you know all about variables and data types and how they work in Python, you are in for a surprise. As you will continue reading this piece, you will come to know that Python variables and data types are somewhat different from their counterparts in other programming languages. There are strings, integers, and numbers, as in C and C++, but things are a little different in Python.
For example, if you are using lists in C language, you will have to interpret it right from the start –allocation management and design memory structure. You will also be required access methods and use search. In other words, you need to declare data types before using them when it comes to languages like C, C++, and Java. On the other hand, you don’t need to declare variables in Python. Lists and other data types in Python are considered an integral part of the programming language.
A variable in Python or, for that matter, any other programming language, can change with time. A computer program, which could be any value, including text, numbers, or other complicated types, uses a memory location for storage.
In symbolic terms, this physical memory location is referred to as a variable. A variable is often seen as a container that stores values. Variables can be accessed and even assigned a new value at any given point when the program is still in the running state.
Variables are often confused with identifiers. Identifiers are the names given to different variables. However, a variable is not just a name. It has a scope, a type, and most importantly, a value associated with it. Also, identifiers can also be used to denote labels, packages, types, functions, and other entities in addition to variables.
Python variables that are used during the length of a module or program are called global variables. On the other hand, variables that are used for a specific method or function are called local variables.
In Python when you want to use the same variable for the rest of your program or module, you declare it a global variable, while if you want to use the variable in a specific function or method, you use a local variable. Python variables have another very remarkable property. Their value, as well as type, can change while the program is running. So, a variable can be assigned a string value and used as such for a while. A little later, however, it could be assigned an integer value.
Python Data Types
Learning how data storage and manipulation work in a programming language is central to develop a thorough understanding of that language. Developers prefer Python because it provides features and ease of use that no other language offer.
An important feature from the host of features that Python provides is dynamic typing. The operation that can be applied to a variable depends on its data type. A variable can only be used for computations when it has a data type against its name. Python is a dynamically typed language as variables are not bound to data types that have been assigned to them.
Standard or Built-In Data Types in Python
The four numeric types supported by Python include integers, float, long, and complex numbers. Integers feature all the numbers, positive and negative, without any decimal point. Floats are real numbers that are represented with a decimal point that separates the fractional and integer parts. Long integers are represented with absolute precision, while complex numbers consist of a real and an imaginary part.
Strings represent arrays of characters. They consist of a list of characters. They aren’t considered too useful for storing data that a computer can use. The length of a string that represents the number of characters it has is one of its most important characteristics. Different algorithms can be used to process strings – that is for sorting, transforming, searching, and comparing them.
Lists are amongst the most versatile and used data types in Python. Lists function in the same way as strings.
Tuples are referred to as containers that have several values separated by commas and mentioned inside parentheses. Tuples are not too different from lists, so it's no wonder they are used in situations in which lists can also be used. The differences between the two – lists contain mutable objects and are enclosed between square brackets while tuples contain immutable objects and are enclosed between parentheses.
Dictionaries in Python enable storage and access to data that has something or the other to do with computers as well as humans. They don’t follow any order and have values and keys. Keys are unique, and values could be integers, floats, strings, or even a combination of these. Dictionaries work like lists in a sense that they can be changed at any given point during run time. They can be easily grown or shrunken.
Learning Python or any other programming language begins by understanding the concepts that are a basic part of its foundation. Variables and data types are those concepts when it comes to learning and successfully implementing Python.
Published at DZone with permission of Shriram K. See the original article here.
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