Generate AR(1) surrogates
AR(1) + ETP simulation routine
Average Spectral Misfit
astrochron: A Computational Tool for Astrochronology
Automatically plot multiple stratigraphic series, with smoothing if desired
Arcsine transformation of stratigraphic series
Generate autoregressive moving-average model
Bandpass filter stratigraphic series
Anchor a floating astrochronology to a radioisotopic age
Obliquity and precession periods of Berger et al. (1992)
Adjust spectrum confidence levels for multiple comparisons
Calculate eccentricity and precession periods in ka, given g and k in arcsec/yr
Bioturbate time series using diffusion model from Guinasso and Schinck (1975), as in Liu et al. (2021)
Apply a constant sedimentation rate model to transform a spatial series to temporal series
Model differential accumulation
Subtract linear trend from stratigraphic series
Apply cosine taper to stratigraphic series
Convolution through Fast Fourier Transform
Evolutive Harmonic Analysis & Evolutive Power Spectral Analysis
Generate eccentricity-tilt-precession models
Generate harmonic model
eTimeOpt: Evolutive implementation of TimeOpt (Meyers, 2015; Meyers, 2019)
Create non-linear response by clipping stratigraphic series
Remove mean value from stratigraphic series
Interactively delete points in plot
Combine multiple vectors
Track eTimeOpt r2 maxima
Apply Hann taper to stratigraphic series
Imbrie and Imbrie (1980) ice sheet model
Download Laskar et al. (2004, 2011a, 2011b) astronomical solutions
Interactively identify points in plot
Extract record from EHA time-frequency output or eAsm output
Flip stratigraphic series
Wiener Deconvolution through Fast Fourier Transform
Divide by linear trend in stratigraphic series
Evolutive Average Spectral Misfit
Apply DPSS taper to stratigraphic series
Log transformation of stratigraphic series
Piecewise linear interpolation of stratigraphic series
Tune stratigraphic series to an astronomical target using graphical interface
Calculate moving window correlation coefficient for two stratigraphic series, using a 'dynamic window'
Apply Gaussian taper to stratigraphic series
Adjust spectral p-values for multiple comparisons
Isolate data from a specified stratigraphic interval
Convert record of local spatial frequency (from EHA) to sedimentation rate curve
List column numbers for each variable
Hilbert transform of stratigraphic series
Track ASM null hypothesis significance level minima in eASM results
Download file from astrochron data server
Query R for color information
Impulse response function calculation
Fit and remove Lowess smoother from stratigraphic series
Pad stratigraphic series with zeros
Lowpass filter stratigraphic series
Mann and Lees (1996) robust red noise MTM analysis
Determine the total power within a given bandwidth
Replace values < 0 with 0
Determine 'dynamic moving window' for stratigraphic series, adjusting for changing sample density to maintain a window of constant duration; output on evenly spaced grid
Robust Locally-Weighted Regression Spectral Background Estimation
Replace values <= 0 with smallest positive value
Multitaper Method Spectral Analysis with Power Law (1/f) fit
Multitaper method spectral analysis
TimeOptPlot: Generate summary figure for TimeOpt analyses
Apply 'ramping' sedimentation rate model to convert time to stratigraphy
Standardize variable in stratigraphic series
Create lithofacies rank series from bed thickness data
Determine 'dynamic moving window' for stratigraphic series, adjusting for changing sample density to maintain a window of constant duration
Remove Gaussian kernel smoother from stratigraphic series
'Dynamic window' moving average, median and variance of stratigraphic series, using evenly spaced spatial/temporal grid
Estimate power law (1/f) fit to power spectrum
TimeOptMCMC: Evaluation of eccentricity-related amplitude modulation and bundling
in paleoclimate data ("TimeOpt"), with uncertainties via Markov-Chain Monte Carlo
TimeOpt: Evaluation of eccentricity-related amplitude modulation and bundling in paleoclimate data
Identify maxima of peaks in series, filter at desired threshold value
Intermediate spectrum test of Thomson et al. (2001)
Create color time-frequency plots from eha results.
Generate noise surrogates from a theoretical power spectrum
Generate cross-plot with kernel density estimates on axes
Monte Carlo simulation for TimeOpt
'Dynamic window' moving assessment of maxima and minima in stratigraphic series
'Dynamic window' moving average, median and variance of stratigraphic series
TimeOptTemplatePlot: Generate summary figure for TimeOptTemplate analyses
Simple periodogram
Simulations for timeOptTemplate
Prewhiten stratigraphic series with autoregressive filter, order selected by Akaike Information Criterion
Astrochronologic testing via the obliquity amplitude modulation approach of Zeeden et al. (2019 submitted).
Ar/Ar Geochronology: Generate an Ar/Ar age spectrum and calculate step-heating plateau age.
Frequency-domain minimal tuning: Use interactive graphical interface and sorting to track frequency drift
A tool to interactively trace peak trajectories on plots
Remove missing entries, sort data, average duplicates
Astrochronologic testing via the precession amplitude modulation approach of Zeeden et al. (2015).
Apply Taner bandpass or lowpass filter to stratigraphic series
Read data matrix from file
Read data from file
Evaluate power spectrum false positive rates via Monte Carlo simulation
Identify minima of troughs in series, filter at desired threshold value
Remove outliers from stratigraphic series
Example stratigraphic model series
Prewhiten stratigraphic series with AR1 filter, using 'standard' or unbiased estimate of rho
Tune stratigraphic series
Bioturbation removal function following the approach of Liu et al (2021)
Ar/Ar Geochronology: calculate weighted mean age, age uncertainty, and other associated statistics/plots (with interactive graphics for data culling).
Generate power law (1/f) noise surrogates
Set up plots
Set default plotting parameters for vertical stratigraphic plots
Integrate sedimentation rate curve to obtain time-space map
Identify optimal spatial/temporal shift to maximize correlation between two stratigraphic/time series.
Summary statistics for stratigraphic series
Estimate correlation coefficient and significance for serially correlated data
Remove stratigraphic levels that contain one or more NAs
Resample stratigraphic series
Generate phase-randomized surrogate series as in Ebisuzaki (1997)
Calculate all possible difference and combinations tones
Synthesize stratigraphy from forcing function
Monte Carlo simulation for TimeOpt, using power law (1/f) noise
Write CSV file
Dynamically explore cross-plot, zoom-in into specified region
Write tab-delimited file
TimeOpt analysis using variable sedimentation models
Frequency-domain minimal tuning: Use interactive graphical interface to trace frequency drift
A tool to interactively select points to track peak trajectories on plots
Remove outliers from stratigraphic series