Used to construct GML 2.0 flog transformer object.

logtGml2_trans(t = 262144, m = 4.5, n = 6, equal.space = FALSE)

Arguments

t

top scale value

m

number of decades

n

desired number of breaks (the actual number will be different depending on the data range)

equal.space

whether breaks at equal-spaced intervals

Value

logtGml2 transformation object

Details

GML 2.0 standard log transform function constructor. The definition is as in the GML 2.0 standard section 6.2 "parametrized logarithmic transformation -- flog" This deviates from standard only in the following way. Before applying the logarithmic transformation, non-positive values are assigned the smallest positive value from the input rather than having undefined values (NA) under the transformation.

Examples

trans.obj <- logtGml2_trans(t = 1e3, m = 1, equal.space = TRUE) data <- 1:1e3 brks.func <- trans.obj[["breaks"]] brks <- brks.func(data) brks # fasinh space displayed at raw data scale
#> [1] 1.000000 3.981072 15.848932 63.095734 251.188643 1000.000000
#transform it to verify it is equal-spaced at transformed scale trans.func <- trans.obj[["transform"]] brks.trans <- trans.func(brks) brks.trans
#> [1] -2.0 -1.4 -0.8 -0.2 0.4 1.0