cutPlot: Divides one or more plots into subplots

In BIOMASS: Estimating Aboveground Biomass and Its Uncertainty in Tropical Forests

Divides one or more plots into subplots

Description

This function divides a plot (or several plots) in subplots and returns the coordinates of the grid. These coordinates are calculated by a bilinear interpolation with the projected corner coordinates as references.

Usage

cutPlot(projCoord, plot, cornerNum, gridsize = 100, dimX = 200, dimY = 200)

Arguments

projCoord	A data frame containing the projected coordinates of plot corners, with X and Y on the first and second column respectively
plot	A vector indicating the plot codes
cornerNum	A vector with corners numbered from 1 to 4 for each plot, numbering must be in clockwise direction
gridsize	The size of the subplots
dimX	A vector indicating the size of the plot on the X axis, in meters and in the relative coordinates system (if a single value is supplied, it will be replicated for all plots)
dimY	A vector indicating the size of the plot on the Y axis, in meters and in the relative coordinates system (if a single value is supplied, it will be replicated for all plots)

Value

Returns a data-frame containing as many rows as there are corners corresponding to the subplots, and the following columns :

• plot: The plot code

• subplot: The automatically generated subplot code

• XRel: The relative coordinates on the X axis (defined by corners 1->4)

• YRel: The relative coordinates on the Y axis (defined by corners 1->2)

• XAbs: The absolute (projected) X coordinates

• YAbs: The absolute (projected) Y coordinates

Author(s)

Arthur PERE

Examples

coord <- data.frame(X = c(0, 200, 0, 200), Y = c(0, 0, 200, 200)) + 5000
cornerNum <- c(1, 2, 4, 3)
plot <- rep("plot1", 4)

cut <- cutPlot(coord, plot, cornerNum, gridsize = 100, dimX = 200, dimY = 200)

# plot the result
plot(coord, main = "example", xlim = c(4900, 5300), ylim = c(4900, 5300), asp = 1)
text(coord, labels = cornerNum, pos = 1)
points(cut$XAbs, cut$YAbs, pch = "+")
legend("bottomright", legend = c("orignal", "cut"), pch = c("o", "+"))

BIOMASS documentation built on April 3, 2025, 6:09 p.m.