Regular expressions are a strange animal. Many students find them difficult to understand – do you? I realized that a major reason for this is simply that they don’t understand the special regex characters. To put it differently: understand the special characters and everything else in the regex space will come much easier to you. … Read more
Python’s built-in callable(object) returns True if you could call the object argument like a function with the trailing parentheses in object(). You can make any object callable by implementing the instance’s __call__() method. For example, callable(callable) returns True because callable is a function object. But callable(3) returns False because an integer is not a function … Read more
Python is ranked as the second most popular programming language in the Tiobe index according to Zdnet.com. Python has gained popularity among the growing tech areas of machine learning and data science—and it has a simple, elegant syntax that is easy to learn. If you want to start learning Python—or you sit on another computer … Read more
Python’s built-in bytes(source) function creates an immutable bytes object initialized as defined in the function argument source. A bytes object is like a string but it uses only byte characters consisting of a sequence of 8-bit integers in the range 0<=x<256. The returned byte object is immutable—you cannot change it after creation. If you plan … Read more
In this article we will explore how to perform interpolations in Python, using the Scipy library. Scipy provides a lot of useful functions which allows for mathematical processing and optimization of the data analysis. More specifically, speaking about interpolating data, it provides some useful functions for obtaining a rapid and accurate interpolation, starting from a … Read more
The following table is an ASCII character table that translates different character codes—such as obtained by Python’s char() function— into the respective symbol. You can find the source of the description here. Note that you can define each number using the decimal, binary, octal, or hexadecimal system—it’s always the same value! Decimal Binary Octal Hexadecimal … Read more
Python’s built-in bytearray() method takes an iterable such as a list of integers between 0 and 256, converts them to bytes between 00000000 and 11111111, and returns a new array of bytes as a bytearray class. Here’s a minimal example that creates a bytearray from three integers stored in a list: The prefix \x escape … Read more
Python’s built-in bool(x) function converts value x to a Boolean value True or False. It uses implicit Boolean conversion on the input argument x. Any Python object has an associated truth value. The bool(x) function takes only one argument, the object for which a Boolean value is desired. Argument x A Python object for which … Read more
Introduction XML is a tool that is used to store and transport data. It stands for eXtensible Markup Language. XML is quite similar to HTML and they have almost the same kind of structure but they were designed to accomplish different goals. XML is designed to transport data while HTML is designed to display data. … Read more
Python’s built-in bin(integer) function takes one integer argument and returns a binary string with prefix “0b”. If you call bin(x) on a non-integer x, it must define the __index__() method that returns an integer associated to x. Otherwise, it’ll throw a TypeError: object cannot be interpreted as an integer. Argument integer An integer value or … Read more
If you’re like me, you’ll regularly sit in front of your code and wonder: how to escape a given character? Challenge: Some characters have a special meaning in Python strings and regular expressions. Say you want to to search for string “(s)” but the regex engine takes the three characters (s) as a matching group. … Read more