data_coercion: coerce different data sources into class 'tprTrees'

In TapeS: Tree Taper Curves and Sorting Based on 'TapeR'

coerce different data sources into class 'tprTrees'

Description

coercion functions to make NFI, segment and 'BDAT' data available as 'tprTrees' objects

Usage

nfi_as_tprtrees(nfi, mapping = NULL)

seg_as_tprtrees(seg, mapping = NULL)

bdat_as_tprtrees(bdat)

Arguments

nfi	data.frame with tree measurements as provided by german NFI
mapping	mapping of column names
seg	data.frame with measured tree segments, see details.
bdat	data.frame holding data to process with rBDAT

Details

The coerced data is automatically checked for validity by the class constructor. For available species codes see tprSpeciesCode.

When coercing NFI (National forest inventory, BWI) data, one need to provide the columns BaTpr (species code), Bhd (Dbh, [mm]), D03, [mm] (diameter in 30% of tree height) and Hoehe (tree height, [dm]). Optionally, one can provide H1 (measurement height of Bhd, [dm]), H2 (measurement height of D03, [dm]) as well as sHt (measurement error of tree height, i.e. standard deviation [dm]); otherwise these are assumed to be 1.3m, 30% of tree height and 0 (zero), respectively.

Additionally, the NFI database stores diameter as [mm] and height as [dm]; it is *not* necessary to transform to [cm] and [m], as the function does this. Equally, sHt [dm] is transformed to sHt [m].

Keep in mind that species codes of NFI are different from the taper models for historical reasons (c.f. BDAT). Use the NFI table ('x_Ba') to map species codes beforehand (see examples).

Sectional measurements provide more information about the trunk of a tree and are usually stored in a different way. They exhibit an arbitrary amount of diameter measurements which also might vary from tree to tree. Hence, seg_as_tprtrees expects a data.frame with columns Id, BaTpr (species code), Dm (diameter measured, [cm]), Hm (height of Dm, [m]) and optionally Ht (height of tree, [m]). Tree height Ht can be included to Dm-Hm-pairs with Dm being zero (e.g. Dm=0, Hm=25). If Ht is given, it gains priority.

coercing object of class 'datBDAT' from R-Package "rBDAT" into class 'tprTrees'

Value

an object of class 'tprTrees', see tprTrees-class

Functions

• nfi_as_tprtrees(): coercion of German NFI data

• seg_as_tprtrees(): coercion of segmented data to class 'tprTrees'

• bdat_as_tprtrees(): coercion of bdat data

See Also

tprTrees-class, tprTrees, tprSpeciesCode

Examples

# NFI data usually stored as integer and units: diameter=[mm] and height=[dm]
nfi <- data.frame(BaTpr=1L, Bhd=300L, D03=270L, Hoehe=250L)
tpr <- nfi_as_tprtrees(nfi)
tpr
tpr@sHt # defaults to 0

# one can provide measurement heights explicitly
nfi <- data.frame(spp=1, Bhd=300, H1=12, D03=270, H=250)
nfi_as_tprtrees(nfi, mapping=c(spp="BaTpr", H="Hoehe"))

# measurement error in height
nfi <- data.frame(BaTpr=1L, Bhd=300L, D03=270L, Hoehe=250L, sHt=15)
tpr <- nfi_as_tprtrees(nfi)
tpr@sHt
## coercing sectional measurements
data(DxHx.df, package = "TapeR")
DxHx.df$BaTpr <- 1 # Norway spruce
segtprtrees <- seg_as_tprtrees(DxHx.df, mapping=c(Dx="Dm", Hx="Hm"))

## extract tree height from Dm-Hm measurements if not given explicitly
DxHx.df$Ht <- NULL # remove height, as already included with Dm=0
segtprtrees <- seg_as_tprtrees(DxHx.df, mapping=c(Dx="Dm", Hx="Hm"))
segtprtrees
if(require(rBDAT)){
  bdt <- buildTree(list(spp=1, D1=30, D2=28, H2=7, H=25))
  bdat_as_tprtrees(bdt)
}

TapeS documentation built on Aug. 8, 2025, 6:21 p.m.