Calculate tree ring index from chronosequence data (year,growth)

Source: R/plot.R

Calculate tree ring index from chronosequence data (year,growth)

TreeRingIndex(ya, spar = 0.8)

Arguments

ya

data frame of chronosequence data (year,growth)

spar

smoothing parameter of spline curve

Value

list spline ; fitting parameter of Spline curve , idx ; data.frame(year,TreeRingIndex)

References

Cook, E., & Peters, K. (1981). The smoothing spline, a new approach to standardising forest interior tree-ring.Trre-ring Bulletin, 41, 45–53.