forecast: holtWinters needs a period (opts.period >= 2)

Warnings reference › forecast.holtWinters.period

Identifier

forecast.holtWinters.period

Raised by

The grid (core)

Since

1.40.0

What happened

Holt-Winters models a repeating season and cannot do so without knowing how long the season is. With no usable period the forecast returns null - nothing is drawn and no series is produced.

The fix

Set period to the number of observations in one season: 12 for monthly data with a yearly cycle, 7 for daily data with a weekly one.

The smallest fix

grid.statistics.forecast({ col: 'sales', method: 'holtWinters', period: 12, horizon: 6 });

Reference

Covered in full at the API reference.