Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Time Series Decomposition function in Python

Time series decomposition is a method that separates a time-series data set into three (or more) components. For example:

x(t) = s(t) + m(t) + e(t) 

where

t is the time coordinate x is the data s is the seasonal component e is the random error term m is the trend 

In R I would do the functions decompose and stl. How would I do this in python?

like image 800
user3084006 Avatar asked Dec 19 '13 02:12

user3084006


People also ask

What is time series decomposition?

Time series decomposition involves thinking of a series as a combination of level, trend, seasonality, and noise components. Decomposition provides a useful abstract model for thinking about time series generally and for better understanding problems during time series analysis and forecasting.

What is decomposition in Python?

Image by Author. Time series decomposition is a technique that splits a time series into several components, each representing an underlying pattern category, trend, seasonality, and noise. In this tutorial, we will show you how to automatically decompose a time series with Python.

What is seasonal_decompose in Python?

In Python, the statsmodels library has a seasonal_decompose() method that lets you decompose a time series into trend, seasonality and noise in one line of code.


1 Answers

I've been having a similar issue and am trying to find the best path forward. Try moving your data into a Pandas DataFrame and then call StatsModels tsa.seasonal_decompose. See the following example:

import statsmodels.api as sm  dta = sm.datasets.co2.load_pandas().data # deal with missing values. see issue dta.co2.interpolate(inplace=True)  res = sm.tsa.seasonal_decompose(dta.co2) resplot = res.plot() 

Three plots produced from above input

You can then recover the individual components of the decomposition from:

res.resid res.seasonal res.trend 

I hope this helps!

like image 149
AN6U5 Avatar answered Oct 05 '22 09:10

AN6U5