eTimeOpt {astrochron} | R Documentation |

## eTimeOpt: Evolutive implementation of TimeOpt (Meyers, 2015; Meyers, 2019)

### Description

eTimeOpt: Evolutive implementation of TimeOpt (Meyers, 2015; Meyers, 2019).

### Usage

```
eTimeOpt(dat,win=dt*100,step=dt*10,sedmin=0.5,sedmax=5,numsed=100,linLog=1,
limit=T,fit=1,fitModPwr=T,flow=NULL,fhigh=NULL,roll=NULL,targetE=NULL,targetP=NULL,
detrend=T,ydir=1,palette=6,ncolors=100,output=1,genplot=T,check=T,verbose=1)
```

### Arguments

`dat` |
Stratigraphic series for astrochronologic assessment. First column should be depth or height (in meters), second column should be data value. |

`win` |
Window size, in meters. |

`step` |
Step size for moving window, in meters. |

`sedmin` |
Minimum sedimentation rate for investigation (cm/ka). |

`sedmax` |
Maximum sedimentation rate for investigation (cm/ka). |

`numsed` |
Number of sedimentation rates to investigate in optimization grid. |

`linLog` |
Use linear or logarithmic scaling for sedimentation rate grid spacing? (0=linear, 1=log; default value is 1) |

`limit` |
Limit evaluated sedimentation rates to region in which full target signal can be recovered? (T or F). |

`fit` |
Test for (1) precession amplitude modulation or (2) short eccentricity amplitude modulation? |

`fitModPwr` |
Include the modulation periods in the spectral fit? (T or F) |

`flow` |
Low frequency cut-off for Taner bandpass (half power point; in cycles/ka) |

`fhigh` |
High frequency cut-off for Taner bandpass (half power point; in cycles/ka) |

`roll` |
Taner filter roll-off rate, in dB/octave. |

`targetE` |
A vector of eccentricity periods to evaluate (in ka). These must be in order of decreasing period, with a first value of 405 ka. |

`targetP` |
A vector of precession periods to evaluate (in ka). These must be in order of decreasing period. |

`detrend` |
Remove linear trend from data series? (T or F) |

`ydir` |
Direction for y-axis in plots (depth,height,time). -1 = values increase downwards (slower plotting), 1 = values increase upwards |

`palette` |
What color palette would you like to use? (1) rainbow, (2) grayscale, (3) blue, (4) red, (5) blue-white-red (if values are negative and positive, white is centered on zero), (6) viridis |

`ncolors` |
Number of colors steps to use in palette. |

`output` |
Which results would you like to return to the console? (0) no output; (1) everything, (2) r^2_envelope, (3) r^2_power, (4) r^2_opt |

`genplot` |
Generate summary plots? (T or F) |

`check` |
Conduct compliance checks before processing? (T or F) In general this should be activated; the option is included for Monte Carlo simulation. |

`verbose` |
Verbose output? (0=nothing, 1=minimal, 2=a little more, 3=everything!) |

### References

S.R. Meyers, 2015,
*The evaluation of eccentricity-related amplitude modulations and bundling in
paleoclimate data: An inverse approach for astrochronologic testing and time scale
optimization*: Paleoceanography, v.30, 1625-1640.

S.R. Meyers, 2019,
*Cyclostratigraphy and the problem of astrochronologic testing*: Earth-Science Reviews
v.190, 190-223.

### See Also

`tracePeak`

,`trackPeak`

,`timeOpt`

,`timeOptSim`

, and `eTimeOptTrack`

### Examples

```
## Not run:
# generate a test signal with precession and eccentricity
ex=cycles(freqs=c(1/405.6795,1/130.719,1/123.839,1/98.86307,1/94.87666,1/23.62069,
1/22.31868,1/19.06768,1/18.91979),end=4000,dt=5)
# convert to meters with a linearly increasing sedimentation rate from 0.01 m/kyr to 0.03 m/kyr
ex=sedRamp(ex,srstart=0.01,srend=0.03)
# interpolate to median sampling interval
ex=linterp(ex)
# evaluate precession & eccentricity power, and precession modulations
res=eTimeOpt(ex,win=20,step=1,fit=1,output=1)
# extract the optimal fits for the power optimization
sedrates=eTimeOptTrack(res[2])
# extract the optimal fits for the envelope*power optimization
sedrates=eTimeOptTrack(res[3])
# you can also interactively track the results using functions 'trackPeak' and 'tracePeak'
# evaluate the results from the power optimization
sedrates=tracePeak(res[2])
sedrates=trackPeak(res[2])
# evaluate the results from the envelope*power optimization
sedrates=tracePeak(res[3])
sedrates=trackPeak(res[3])
# evaluate precession & eccentricity power, and short-eccentricity modulations
eTimeOpt(ex,win=20,step=1,fit=2,output=0)
## End(Not run)
```

*astrochron*version 1.3 Index]