Book Image

Python Data Analysis Cookbook

By : Ivan Idris
Book Image

Python Data Analysis Cookbook

By: Ivan Idris

Overview of this book

Data analysis is a rapidly evolving field and Python is a multi-paradigm programming language suitable for object-oriented application development and functional design patterns. As Python offers a range of tools and libraries for all purposes, it has slowly evolved as the primary language for data science, including topics on: data analysis, visualization, and machine learning. Python Data Analysis Cookbook focuses on reproducibility and creating production-ready systems. You will start with recipes that set the foundation for data analysis with libraries such as matplotlib, NumPy, and pandas. You will learn to create visualizations by choosing color maps and palettes then dive into statistical data analysis using distribution algorithms and correlations. You’ll then help you find your way around different data and numerical problems, get to grips with Spark and HDFS, and then set up migration scripts for web mining. In this book, you will dive deeper into recipes on spectral analysis, smoothing, and bootstrapping methods. Moving on, you will learn to rank stocks and check market efficiency, then work with metrics and clusters. You will achieve parallelism to improve system performance by using multiple threads and speeding up your code. By the end of the book, you will be capable of handling various data analysis techniques in Python and devising solutions for problem scenarios.
Table of Contents (23 chapters)
Python Data Analysis Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Glossary
Index

Creating heatmaps


Heat maps visualize data in a matrix using a set of colors. Originally, heat maps were used to represent prices of financial assets, such as stocks. Bokeh is a Python package that can display heatmaps in an IPython notebook or produce a standalone HTML file.

Getting ready

I have Bokeh 0.9.1 via Anaconda. The Bokeh installation instructions are available at http://bokeh.pydata.org/en/latest/docs/installation.html (retrieved July 2015).

How to do it...

  1. The imports are as follows:

    from collections import OrderedDict
    from dautil import data
    from dautil import ts
    from dautil import plotting
    import numpy as np
    import bokeh.plotting as bkh_plt
    from bokeh.models import HoverTool
  2. The following function loads temperature data and groups it by year and month:

    def load():
        df = data.Weather.load()['TEMP']
        return ts.groupby_year_month(df)
  3. Define a function that rearranges data in a special Bokeh structure:

    def create_source():
        colors = plotting.sample_hex_cmap()
    
        month = []
     ...