Sometimes we want to change the ordering of a DataFrame's columns. Maybe you are saving your data and require the columns to be in a certain order, or you may have a large number of columns and want a few of them to be visible whenever viewing your DataFrame in an interactive session, so you … Continue reading Basic Pandas: Moving a DataFrame column
Tag: pandas
Basic Pandas: Renaming a DataFrame column
A very common need in working with pandas DataFrames is to rename a column. Maybe the columns were supplied by a data source like a CSV file and they need cleanup. Or maybe you just changed your mind during an interactive session. Let's look at how you can do this, because there's more than one … Continue reading Basic Pandas: Renaming a DataFrame column
Basic Pandas: How to add a column to a DataFrame
Pandas is one of my favorite Python libraries, and I use it every day. A very common action is to add a column to a DataFrame. This is a pretty basic task. I'm going to look at a few examples to better show what is happening when we add a column, and how we need … Continue reading Basic Pandas: How to add a column to a DataFrame
3 ways to get historical market data from IEX Cloud
IEX Cloud is a service offering financial data. They offer a wide variety of data sets, both for historical and real-time data. Those of us interested in financial data, whether for trading or research, are always looking for good data sources, especially for clean and complete data. This post will show you three ways to … Continue reading 3 ways to get historical market data from IEX Cloud
A pandas.DataFrame.apply example
I recently saw a question about pandas.DataFrame.apply and realized that when I first started using Pandas I would often attempt to solve problems with apply when a vectorized solution was what I should have been using instead. Let's say that you have an existing function to calculate the present value of an investment that takes … Continue reading A pandas.DataFrame.apply example