Book Image

Data Science Algorithms in a Week - Second Edition

By : David Natingga
Book Image

Data Science Algorithms in a Week - Second Edition

By: David Natingga

Overview of this book

Machine learning applications are highly automated and self-modifying, and continue to improve over time with minimal human intervention, as they learn from the trained data. To address the complex nature of various real-world data problems, specialized machine learning algorithms have been developed. Through algorithmic and statistical analysis, these models can be leveraged to gain new knowledge from existing data as well. Data Science Algorithms in a Week addresses all problems related to accurate and efficient data classification and prediction. Over the course of seven days, you will be introduced to seven algorithms, along with exercises that will help you understand different aspects of machine learning. You will see how to pre-cluster your data to optimize and classify it for large datasets. This book also guides you in predicting data based on existing trends in your dataset. This book covers algorithms such as k-nearest neighbors, Naive Bayes, decision trees, random forest, k-means, regression, and time-series analysis. By the end of this book, you will understand how to choose machine learning algorithms for clustering, classification, and regression and know which is best suited for your problem
Table of Contents (16 chapters)
Title Page
Packt Upsell
Contributors
Preface
Glossary of Algorithms and Methods in Data Science
Index

Input and output


Let's look at how to pass arguments to a Python program and how to read and write to a file.

Program arguments

We can pass arguments to a program from the command line.

Input:

source_code/appendix_c_python/example14_arguments.py
#Import the system library in order to use the argument list.
import sys

print 'The number of the arguments given is', len(sys.argv),'arguments.'
print 'The argument list is ', sys.argv, '.'

 

Output:

$ python example14_arguments.py arg1 110
The number of the arguments given is 3 arguments.
The argument list is  ['example14_arguments.py', 'arg1', '110'] .

Reading and writing a file

The following program will write two lines to the test.txt file, then read them, and finally, print them to the output.

Input:

# source_code/appendix_c_python/example15_file.py
#write to the file with the name "test.txt"
file = open("test.txt","w") 
file.write("first line\n")
file.write("second line")
file.close()

#read the file
file = open("test.txt","r")
print file.read()

Output:

$ python example15_file.py 
first line
second line