Target periodogram from an astronomical time series (e.g. La2004 ETP)

Periodogram of an astronomical series, or of an ETP series built from eccentricity, obliquity and precession as in gentarget.m.

Usage

coco_target_from_series(
  time_kyr,
  value = NULL,
  ecc = NULL,
  obl = NULL,
  prec = NULL,
  ne = 1,
  nt = 0.6,
  np = 0.5,
  f1 = 0,
  f2 = 0.06,
  pad = 10000
)

Arguments

time_kyr: Time axis of the astronomical series, in kyr (numeric vector, evenly spaced; the series is sorted by it and its first step is used as the sampling interval). Required, no default.
value: Astronomical series to use as target (numeric vector, same length as time_kyr), e.g. an ETP series; NULL builds an ETP series from ecc, obl and prec. Default=NULL.
ecc: Eccentricity series (numeric vector, same length and order as time_kyr), used with obl and prec instead of value: the ETP series is ne * z(ecc) + nt * z(obl) - np * z(prec), with z the standardisation to zero mean and unit standard deviation (as in Acycle gentarget.m). Default=NULL.
obl: Obliquity series (numeric vector, same length and order as time_kyr), used to build the ETP series when value is NULL. Default=NULL.
prec: Precession (index) series (numeric vector, same length and order as time_kyr), used with a negative sign to build the ETP series when value is NULL. Default=NULL.
ne: Weight of the standardised eccentricity in the ETP series (numeric). Default=1.
nt: Weight of the standardised obliquity in the ETP series (numeric). Default=0.6.
np: Weight of the standardised precession in the ETP series (numeric). Default=0.5.
f1: Lowest frequency of the target that is returned, in cycles/kyr (numeric, >= 0). Default=0.
f2: Highest frequency of the target that is returned, in cycles/kyr (numeric, > f1). Default=0.06.
pad: Length (number of points) to which the series is zero-padded for the periodogram (integer; at least the series length is used); a larger value gives a finer frequency grid. Default=10000.

Value

two-column matrix: frequency (cycles/kyr), power