Overview on extracted features¶
tsfresh calculates a comprehensive number of features. All feature calculators are contained in the
tsfresh.feature_extraction.feature_calculators |
This module contains the feature calculators that take time series as input and calculate the values of the feature. |
submodule.
The following, exhaustive list contains all features that are calculated in the current version of tsfresh:
abs_energy (x) |
Returns the absolute energy of the time series which is the sum over the squared values |
absolute_sum_of_changes (x) |
Returns the sum over the absolute value of consecutive changes in the series x |
agg_autocorrelation (x, param) |
Calculates the value of an aggregation function ![]() |
agg_linear_trend (x, param) |
Calculates a linear least-squares regression for values of the time series that were aggregated over chunks versus the sequence from 0 up to the number of chunks minus one. |
approximate_entropy (x, m, r) |
Implements a vectorized Approximate entropy algorithm. |
ar_coefficient (x, param) |
This feature calculator fits the unconditional maximum likelihood of an autoregressive AR(k) process. |
augmented_dickey_fuller (x, param) |
The Augmented Dickey-Fuller test is a hypothesis test which checks whether a unit root is present in a time series sample. |
autocorrelation (x, lag) |
Calculates the autocorrelation of the specified lag, according to the formula [1] |
binned_entropy (x, max_bins) |
First bins the values of x into max_bins equidistant bins. |
c3 (x, lag) |
This function calculates the value of |
change_quantiles (x, ql, qh, isabs, f_agg) |
First fixes a corridor given by the quantiles ql and qh of the distribution of x. |
cid_ce (x, normalize) |
This function calculator is an estimate for a time series complexity [1] (A more complex time series has more peaks, valleys etc.). |
count_above (x, t) |
Returns the percentage of values in x that are higher than t |
count_above_mean (x) |
Returns the number of values in x that are higher than the mean of x |
count_below (x, t) |
Returns the percentage of values in x that are lower than t |
count_below_mean (x) |
Returns the number of values in x that are lower than the mean of x |
cwt_coefficients (x, param) |
Calculates a Continuous wavelet transform for the Ricker wavelet, also known as the “Mexican hat wavelet” which is |
energy_ratio_by_chunks (x, param) |
Calculates the sum of squares of chunk i out of N chunks expressed as a ratio with the sum of squares over the whole series. |
fft_aggregated (x, param) |
Returns the spectral centroid (mean), variance, skew, and kurtosis of the absolute fourier transform spectrum. |
fft_coefficient (x, param) |
Calculates the fourier coefficients of the one-dimensional discrete Fourier Transform for real input by fast |
first_location_of_maximum (x) |
Returns the first location of the maximum value of x. |
first_location_of_minimum (x) |
Returns the first location of the minimal value of x. |
friedrich_coefficients (x, param) |
Coefficients of polynomial ![]() |
has_duplicate (x) |
Checks if any value in x occurs more than once |
has_duplicate_max (x) |
Checks if the maximum value of x is observed more than once |
has_duplicate_min (x) |
Checks if the minimal value of x is observed more than once |
index_mass_quantile (x, param) |
Those apply features calculate the relative index i where q% of the mass of the time series x lie left of i. |
kurtosis (x) |
Returns the kurtosis of x (calculated with the adjusted Fisher-Pearson standardized moment coefficient G2). |
large_standard_deviation (x, r) |
Boolean variable denoting if the standard dev of x is higher than ‘r’ times the range = difference between max and min of x. |
last_location_of_maximum (x) |
Returns the relative last location of the maximum value of x. |
last_location_of_minimum (x) |
Returns the last location of the minimal value of x. |
length (x) |
Returns the length of x |
linear_trend (x, param) |
Calculate a linear least-squares regression for the values of the time series versus the sequence from 0 to length of the time series minus one. |
linear_trend_timewise (x, param) |
Calculate a linear least-squares regression for the values of the time series versus the sequence from 0 to length of the time series minus one. |
longest_strike_above_mean (x) |
Returns the length of the longest consecutive subsequence in x that is bigger than the mean of x |
longest_strike_below_mean (x) |
Returns the length of the longest consecutive subsequence in x that is smaller than the mean of x |
max_langevin_fixed_point (x, r, m) |
Largest fixed point of dynamics :math:argmax_x {h(x)=0}` estimated from polynomial ![]() |
maximum (x) |
Calculates the highest value of the time series x. |
mean (x) |
Returns the mean of x |
mean_abs_change (x) |
Returns the mean over the absolute differences between subsequent time series values which is |
mean_change (x) |
Returns the mean over the differences between subsequent time series values which is |
mean_second_derivative_central (x) |
Returns the mean value of a central approximation of the second derivative |
median (x) |
Returns the median of x |
minimum (x) |
Calculates the lowest value of the time series x. |
number_crossing_m (x, m) |
Calculates the number of crossings of x on m. |
number_cwt_peaks (x, n) |
This feature calculator searches for different peaks in x. |
number_peaks (x, n) |
Calculates the number of peaks of at least support n in the time series x. |
partial_autocorrelation (x, param) |
Calculates the value of the partial autocorrelation function at the given lag. |
percentage_of_reoccurring_datapoints_to_all_datapoints (x) |
Returns the percentage of unique values, that are present in the time series more than once. |
percentage_of_reoccurring_values_to_all_values (x) |
Returns the ratio of unique values, that are present in the time series more than once. |
quantile (x, q) |
Calculates the q quantile of x. |
range_count (x, min, max) |
Count observed values within the interval [min, max). |
ratio_beyond_r_sigma (x, r) |
Ratio of values that are more than r*std(x) (so r sigma) away from the mean of x. |
ratio_value_number_to_time_series_length (x) |
Returns a factor which is 1 if all values in the time series occur only once, and below one if this is not the case. |
sample_entropy (x) |
Calculate and return sample entropy of x. |
set_property (key, value) |
This method returns a decorator that sets the property key of the function to value |
skewness (x) |
Returns the sample skewness of x (calculated with the adjusted Fisher-Pearson standardized moment coefficient G1). |
spkt_welch_density (x, param) |
This feature calculator estimates the cross power spectral density of the time series x at different frequencies. |
standard_deviation (x) |
Returns the standard deviation of x |
sum_of_reoccurring_data_points (x) |
Returns the sum of all data points, that are present in the time series more than once. |
sum_of_reoccurring_values (x) |
Returns the sum of all values, that are present in the time series more than once. |
sum_values (x) |
Calculates the sum over the time series values |
symmetry_looking (x, param) |
Boolean variable denoting if the distribution of x looks symmetric. |
time_reversal_asymmetry_statistic (x, lag) |
This function calculates the value of |
value_count (x, value) |
Count occurrences of value in time series x. |
variance (x) |
Returns the variance of x |
variance_larger_than_standard_deviation (x) |
Boolean variable denoting if the variance of x is greater than its standard deviation. |
variation_coefficient (x) |
Returns the variation coefficient (standard error / mean, give relative value of variation around mean) of x. |