nearPith: Calibrate ring-width series

Description Usage Arguments Details Value Author(s) References Examples

Description

This function can calibrate the ring-width series using arcs of inner rings.

Usage

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nearPith(ring.data, inner.arc = TRUE, last.yr = NULL, 
         color = 'black', border.type = 16, label.cex = 1.5)

Arguments

ring.data

A magick image object produced by imgInput.

inner.arc

A logical value indicating whether to calibrate the ring-width series using the arcs of inner rings. See details below.

last.yr

NULL or an integer giving the year of formation of the left-most ring. If NULL, borders numbers (starting from 1) ares used instead of the year.

color

Color for labels.

border.type

Symbol for ring borders. See pch in points for possible values and their shapes.

label.cex

The magnification to be used for years and ring numbers.

Details

This function allows the user to create a path, and visually identify ring borders by clicking on the graphical window.

Value

A data frame of the calibrated ring-width series.

Author(s)

Jingning Shi

References

Duncan R. (1989) An evaluation of errors in tree age estimates based on increment cores in Kahikatea (Dacrycarpus dacrydiodes). New Zealand Natural Sciences 16(4), 1-37.

Examples

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img.path <- system.file("arc.png", package = "MtreeRing")

## Read and plot the image:
t1 <- imgInput(img = img.path, dpi = 1200)

## Use the arcs of inner rings to calibrate ring-width series:
t2 <- nearPith(ring.data = t1, inner.arc = TRUE, last.yr = 2016) 


## Try another method to measure ring widths:
t3 <- nearPith(ring.data = t1, inner.arc = FALSE, last.yr = 2016) 

JingningShi/GifRepo documentation built on May 14, 2019, 10:59 p.m.