fe_ccircle_spatial_notrees: User Friendly Construction of an *fe_ccircle_spatial_notrees*...

In ForestElementsR: Data Structures and Functions for Working with Forest Data

User Friendly Construction of an fe_ccircle_spatial_notrees Object from a List of Data Frames

Description

fe_ccircle_spatial_notrees() provides a user-friendly interface for the constructor new_fe_ccircle_spatial_notrees. While the constructor does not prevent users from creating malformed new_fe_ccircle_spatial_notrees objects, new_fe_ccircle_spatial_notrees does everything to achieve a well-defined object mostly based on an initial list of data.frames that might be, e.g. drawn out of a user's own data base.

Usage

fe_ccircle_spatial_notrees(
  x,
  time_yr_name = "time_yr",
  circle_frame_name = "circle_definition",
  center_coord = "center_coordinate",
  small_trees_name = "small_trees",
  stand_id = "my_fe_ccircle_spatial_notrees"
)

Arguments

x	Named list to be coerced into the goal object.
time_yr_name	name of the element of x which contains the required time information, i.e. a single (calendar) year or vector of years in order to give the object a time relation. If small tree information is present (i.e. the small tree data frame is not empty), time_yr must absolutely match with the time_yr column of this data frame.
circle_frame_name	Name of the data frame in x that contains the definition of the concentric circles. It must contain the lower and the upper dbh limits, the circle area in Ha, and the slope in degrees. If the slope is not given it will be set to 0.
center_coord	Name of the sf object that contains the center coordinate of the circles with coordinate reference system (either Gauss Kruger or UTM). If it is not provided the center will be c(0,0) by the default
small_trees_name	Name of the object that contains the information regarding the small trees (generally those trees that do no have any dbh because of having a height below 1.3 m). This object is still experimental, so the only requirement for it is that it has to be a data frame without any further specification. Useful standard information in this data frame are the tree id, the height and represenation area.
stand_id	arbitrary id of the stand (character, default: "my_fe_ccircle_spatial")

Details

An object of class fe_ccircle_spatial_notrees is a child object of fe_ccircle_spatial which, however does not contain trees which are big enough to have a dbh. So, in contrast to fe_ccircle_spatial objects, where the elements trees, and tree_positions must be data frames, both are NULL in this class. The class fe_ccircle_spatial_notrees has been designed for covering a comparably rare case, i.e. an inventory point where no regular trees (trees that are big enough to have a dbh), but possibly small trees are present. The input object x to fe_ccircle_spatial must be a list that follows the same conventions as the input object of fe_ccircle_spatial, except that no tree data frame is required. If it does exist, it will be ignored. In addition to the input object of fe_ccircle_spatial, there is one additional list element needed which defines a single (calendar) year or a vector of years in order to give the object a time relation. If small tree information is present (i.e. the small tree data frame is not empty), time_yr must absolutely match with the time_yr column of this data frame.

Value

If the user input allows to construct a well-defined fe_ccircle_spatial_notrees object, this object will be returned. If not, the function will terminate with an error.

Examples

# Transform the example data collection mm_forest_1_raw (could e.g. have
# been drawn out of a user's data base) into an fe_ccircle_spatial_notrees
# object. This means, that in the resulting data frame the trees and their
# positions are ignored.
notrees_example <- spruce_pine_ccircle_raw |>
  fe_ccircle_spatial_notrees()

plot(notrees_example)

ForestElementsR documentation built on April 3, 2025, 7:47 p.m.