utils.resample.downsample

utils.resample.downsample(
    series,
    method='exponential',
    param=None,
    return_index=False,
    seed=None,
)

Downsample a Pyleoclim series by drawing random time increments.

Simulates irregular sampling by generating random index increments from a chosen probability distribution and selecting the corresponding time points from the original series.

Parameters

series : pyleoclim.Series: The time series to downsample.
method : str = 'exponential': Probability distribution used to draw index increments. One of: - 'exponential' — exponential distribution; param is a 1-element list [scale] (i.e. mean gap size). - 'poisson' — Poisson distribution; param is [rate]. - 'pareto' — Pareto distribution; param is [shape, scale]. - 'random_choice' — discrete distribution; param is [values, probabilities] where both arrays have the same length. Default 'exponential'.
param : list or None = None: Parameter(s) for the chosen distribution. Default [1] (exponential with scale 1).
return_index : bool = False: If True, return the integer index array instead of a new series. Default False.
seed : int or None = None: Seed for the random number generator. Pass an integer for reproducible results. Default None.

Returns

downsampled : pyleoclim.Series or list of int: Downsampled series (return_index=False) or list of selected indices (return_index=True).

Raises

: ValueError: If method is not recognised, or param has the wrong shape for the chosen distribution.

Examples

import matplotlib.pyplot as plt
import pyleoclim as pyleo
from climatecritters.utils.resample import downsample

soi = pyleo.utils.load_dataset('SOI')
soi_sparse = downsample(soi, method='exponential', param=[3.0], seed=42)
soi_sparse.plot()
plt.savefig('docs/reference/figures/downsample_example.png',
            dpi=150, bbox_inches='tight')