stemMappingExtension: Extend stem mapping to a target area and shape.
In bcgov/BCForestGroundSample: BC forest ground sample compilation

Description Usage Arguments Value Author(s) Examples

The function cuts a circle stem map into a largest hexagon in circle and extends this hexagon to a target area and shape. This is a generic function.

1 2	stemMappingExtension(objectID, azimuth, distance, radius = 11.28, targetArea = 1, targetShape = "square", randomRotate = FALSE)

`objectID`	character, A object's ID, e.g., a tree's ID.
`azimuth`	numeric, Azimuth of a object from the north. It should be between 0 to 360.
`distance`	numeric, Distance between a object and the centre of the circle.
`radius`	numeric, Radius of the circle. If missing, `11.28` will be used, as it presents the radius of a circle for big trees (i.e., trees DBH >= 9).
`targetArea`	numeric, Defines the area you may want to extend. The unit of this input is `ha`. Default is 1 ha.
`targetShape`	character, Defines the shape of the target area. It currently supports `circle` and `square`. The default is `square`.
`randomRotate`	logical, Defines whether need to random rotate the hexagon when merge into a `targetArea`. The default is `FALSE`.

A table contains the x and y for all the objects in the extended area.

Yong Luo

## Not run: 
## randomly generate some trees
library(data.table)
smallplottrees <- data.table(tree_id = 1:20,
                             angle = runif(20, min = 0, max = 360),
                             distance = runif(20, min = 0, max = 5.6))
## extend it to 1 ha
treelist_smallplot <- stemMappingExtension(objectID = smallplottrees$tree_id,
                                           azimuth = smallplottrees$angle,
                                           distance = smallplottrees$distance,
                                           radius = 5.64,
                                           randomRotate = TRUE)


bigplottrees <- data.table(tree_id = 1:20,
                           angle = runif(20, min = 0, max = 360),
                           distance = runif(20, min = 0, max = 11.28))
## extend it to 1 ha
treelist_bigplot <- stemMappingExtension(objectID = bigplottrees$tree_id,
                                         azimuth = bigplottrees$angle,
                                         distance = bigplottrees$distance,
                                         radius = 11.28)
treelist_smallplot[, source := "smallplot"]
treelist_bigplot[, source := "bigplot"]


alltreelist <- rbind(treelist_bigplot, treelist_smallplot)


alltreeplot <- ggplot(data = alltreelist, aes(x, y))+
 geom_point(aes(col = factor(source)))


## End(Not run)