Book Image

Python Data Analysis - Third Edition

By : Avinash Navlani, Ivan Idris
5 (1)
Book Image

Python Data Analysis - Third Edition

5 (1)
By: Avinash Navlani, Ivan Idris

Overview of this book

Data analysis enables you to generate value from small and big data by discovering new patterns and trends, and Python is one of the most popular tools for analyzing a wide variety of data. With this book, you’ll get up and running using Python for data analysis by exploring the different phases and methodologies used in data analysis and learning how to use modern libraries from the Python ecosystem to create efficient data pipelines. Starting with the essential statistical and data analysis fundamentals using Python, you’ll perform complex data analysis and modeling, data manipulation, data cleaning, and data visualization using easy-to-follow examples. You’ll then understand how to conduct time series analysis and signal processing using ARMA models. As you advance, you’ll get to grips with smart processing and data analytics using machine learning algorithms such as regression, classification, Principal Component Analysis (PCA), and clustering. In the concluding chapters, you’ll work on real-world examples to analyze textual and image data using natural language processing (NLP) and image analytics techniques, respectively. Finally, the book will demonstrate parallel computing using Dask. By the end of this data analysis book, you’ll be equipped with the skills you need to prepare data for analysis and create meaningful data visualizations for forecasting values from data.
Table of Contents (20 chapters)
1
Section 1: Foundation for Data Analysis
6
Section 2: Exploratory Data Analysis and Data Cleaning
11
Section 3: Deep Dive into Machine Learning
15
Section 4: NLP, Image Analytics, and Parallel Computing

Reading and writing data from HDF5

HDF stands for Hierarchical Data Format. HDF is designed to store and manage large amounts of data with high performance. It offers fast I/O processing and storage of heterogeneous data. There are various HDF file formats available, such as HDF4 and HDF5. HDF5 is the same as a dictionary object that reads and writes pandas DataFrames. It uses the PyTables library's read_hdf() function for reading the HDF5 file and the to_hdf() function for writing:

# Write DataFrame to hdf5
df.to_hdf('employee.h5', 'table', append=True)

In the preceding code example, we have written the HDF file format using the to_hdf() method. 'table' is a format parameter used for the table format. Table format may perform slower but offers more flexible operations, such as searching and selecting. The append parameter is used to append input data onto the existing data file:

# Read a hdf5 file
df=pd.read_hdf('employee.h5', 'table&apos...