How To Add a New Column to Using a Dictionary in Pandas Data Frame ?: Pandas Tutorial

Pandas library in Python has a really cool function called map that lets you manipulate your pandas data frame much easily. Pandas’ map function lets you add a new column with values from a dictionary if the data frame has a column matching the keys in the dictionary. Adding a New Column Using keys from […]

How to Compute Executing Time in Python?

It is really good to know whether the code you wrote is efficient or fast. We can test that by checking how long it takes to execute certain commands, or functions. Computing Execution Time With “time” Module One way to get the execution time is to use the built-in time module and its function time.time. […]

5 Examples Using Dict Comprehension in Python

List Comprehension is really a handy and faster way to write for loops in Python in just a single line of code. The idea of comprehension is not just unique to lists in Python. Dictionaries, one of the commonly used data structures in data science, can also do comprehension. This is called dict comprehension or […]

How to Load a Massive File as small chunks in Pandas?

The longer you work in data science, the higher the chance that you might have to work with a really big file with thousands or millions of lines. Trying to load all the data at once in memory will not work as you will end up using all of your RAM and crash your computer. […]

7 Tips to Read a CSV File as Pandas Data Frame

Pandas is one of the popular Python package for manipulating data frames. Pandas is built on top of NumPy and thus it makes data manipulation fast and easy. Here are 7 basic options to learn to load a CSV file in pandas as data frame. Load pandas package Let us first load the pandas package. […]

Getting Started with Lambda Functions in Python

Python lets you create a function on the go, but without really assigning a name to the function. These “anonymous” functions are called “Lambda Functions”. One typically writes a lambda function on the fly, if one wants to write a function for one-time use. Lambda Functions come handy in a variety of situations and are […]

12 Basic Commands with NumPy Array

NumPy (pronounced as Num-pee or Num-pai) is one of the important python packages (other being SciPy) for scientific computing. NumPy offers fast and flexible data structures for multi-dimensional arrays and matrices with numerous mathematical functions/operations associated with it. Core data structure in NumPy is “ndarray”, short for n-dimesional array for storing numeric values. Let us […]

How to Create Pandas Dataframe from Multiple Lists? Pandas Tutorial

NumPy is fantastic for numerical data. One can really do powerful operations with numerical data easily and much faster. However, if your data is of mixed type, like some columns are strings while the others are numeric, using data frame with Pandas is the best option. How to Create Pandas Dataframe from lists? Let us […]

How to read a numerical data/file in Python with numpy?

Often you may need to read a file containing numerical data in Python for. One of the options is to import the file/data in Python is use Python’s NumPy library. There are number of advantages to use NumPy. NumPy is designed to deal with numerical data, it is fast and it has loads of built-in […]

How to read entire text file in Python?

Often one might need to read the entire content of a text file (or flat file) at once in python. In this post, we showed an example of reading the whole file and reading a text file line by line. Here is another way to import the entire content of a text file.