IPEC (version 1.1.0)

leaves: Leaf Data of Parrotia subaequalis (Hamamelidaceae)

Description

The data consist of the area, length and width of the leaves of 10 geographical populations of P. subaequalis collected in Southern China from July to September, 2016.

Usage

data(leaves)

Details

In the data set, there are four variables: PopuCode, Length, Width and Area. PopuCode is used to save the number codes of different geographical populations; Length is used to save the scanned leaf length data (cm); Width is used to save the scanned leaf width data (cm); Area is used to save the scanned leaf area data (cm squared).

References

Wang, P., Ratkowsky, D.A., Xiao, X., Yu, X., Su, J., Zhang, L. and Shi, P. (2018) Taylor's power law for leaf bilateral symmetry. Forests 9, 500. tools:::Rd_expr_doi("10.3390/f9080500")

Examples

data(leaves)
attach(leaves)
# Choose a geographical population (see Table S1 in Wang et al. [2018] for details)
# 1: AJ; 2: HN; 3: HW; 4: HZ; 5: JD; 
# 6: JS; 7: SC; 8: TC; 9: TT; 10: TX
ind <- 1
L   <- Length[PopuCode == ind]
W   <- Width[PopuCode == ind] 
A   <- Area[PopuCode == ind]
x   <- L*W
fit <- lm(A ~ x-1)
summary(fit)

# Show the leaf areas of the 10 geographical populations
dev.new()
boxplot(Area~PopuCode, cex=1.5, cex.lab=1.5, cex.axis=1.5, 
        col="grey70", xlab=expression(bold("Population code")), 
        ylab=expression(bold(paste("Leaf area (cm", ""^{"2"}, ")", sep=""))),
        ylim=c(0, 50), xaxs="i", yaxs="i", las=1)