Book Image

Python Data Analysis - Second Edition

By : Ivan Idris
Book Image

Python Data Analysis - Second Edition

By: Ivan Idris

Overview of this book

Data analysis techniques generate useful insights from small and large volumes of data. Python, with its strong set of libraries, has become a popular platform to conduct various data analysis and predictive modeling tasks. With this book, you will learn how to process and manipulate data with Python for complex analysis and modeling. We learn data manipulations such as aggregating, concatenating, appending, cleaning, and handling missing values, with NumPy and Pandas. The book covers how to store and retrieve data from various data sources such as SQL and NoSQL, CSV fies, and HDF5. We learn how to visualize data using visualization libraries, along with advanced topics such as signal processing, time series, textual data analysis, machine learning, and social media analysis. The book covers a plethora of Python modules, such as matplotlib, statsmodels, scikit-learn, and NLTK. It also covers using Python with external environments such as R, Fortran, C/C++, and Boost libraries.
Table of Contents (22 chapters)
Python Data Analysis - Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
Key Concepts
Online Resources

Neural networks


Artificial neural networks (ANN) are models inspired by the animal brain (highly evolved animals). A neural network is a network of neurons-units with inputs and outputs. For example, the input of a neuron can be a value related to the pixel of an image and the output of a neuron can be passed to another neuron and then another, and so on, thus creating a multilayered network. Neural networks contain adaptive elements, making them suitable to deal with nonlinear models and pattern recognition problems. We will again try to predict whether it is going to rain based on day-of-the-year and previous day values. Let's use the theanets Python library, which can be installed as follows:

$ pip3 install theanets nose_parameterized

One of the technical reviewers encountered an error, which was resolved by updating NumPy and SciPy. We first create an Experiment corresponding to a neural network and then train the network. Create a network with two input neurons and one output neuron...