Feature Calculation¶
Feature naming¶
tsfresh enforces a strict naming of the created features, which you have to follow whenever you create new feature
calculators.
This is due to the tsfresh.feature_extraction.settings.from_columns()
method which needs to
deduce the following information from the feature name
- the time series that was used to calculate the feature
- the feature calculator method that was used to derive the feature
- all parameters that have been used to calculate the feature (optional)
Hence, to enable the tsfresh.feature_extraction.settings.from_columns()
to deduce all the
necessary conditions, the features will be named in the following format
{time_series_name}__{feature_name}__{parameter name 1}_{parameter value 1}__[..]__{parameter name k}_{parameter value k}
(Here we assumed that {feature_name} has k parameters).
Examples for feature naming¶
So for example the following feature name
temperature_1__quantile__q_0.6
is the value of the feature tsfresh.feature_extraction.feature_calculators.quantile()
for the time series
`temperature_1`
and a parameter value of q=0.6
. On the other hand, the feature named
Pressure 5__cwt_coefficients__widths_(2, 5, 10, 20)__coeff_14__w_5
denotes the value of the feature tsfresh.feature_extraction.feature_calculators.cwt_coefficients()
for
the time series `Pressure 5`
under parameter values of widths=(2, 5, 10, 20)
, coeff=14
and w=5
.