Time Series Decomposition

[ParthivNaresh]

As a developer, I wish I could use EvalML to decompose time series data into trend, seasonal, and residual values. These would be useful for graphing purposes and for leveraging in other time series tools down the line.

trend, seasonal, residuals = decompose(y)

[chukarsten]

File separate issues for a graphing function and/or estimators for this. Maybe it becomes an epic of its own, depends on what we want as a result of planning time series v.2 epic.