# Weise's Dominant Height The dominant height after Weise is the quadratic mean height of the 20% biggest trees in a stand. In contrast to the dominant height `h_100` it is well defined not only in monospecific stands, but also in mixed stands. ```r h_dom_weise(h, d, n_rep = 1) ``` ## Arguments - `h`: vector of tree height values to calculate Weise's dominant height from - `d`: vector of stem diameters at breast height corresponding to h, must therefore have the same length as h - `n_rep`: vector of representation numbers (typically the number of trees per ha corresponding to the diameter at the same position), will be used as individual weights for each height, together with the squared diameters d. If n_rep has length 1, it will be recycled to the length of d. Otherwise, if the length of n_rep does not correspond to the length of d, the function will terminate with an error. ## Returns The value of Weise's dominant diameter resulting from the input data ## Examples ```r # A sample of trees from an angle count sample , where each # tree represents a basal area of 4 m²/ha d_cm <- c(12, 13, 25, 27, 28, 26, 26.1, 32, 35, 31, 42) n_rep_ha <- 4 / ((d_cm / 100)^2 * pi / 4) # representation number of each tree dq_cm <- d_q(d_cm, n_rep_ha) h_m <- 0.9 * dq_cm * (d_cm / dq_cm)^0.8 # quick plausible height estim. h_dom_weise(h_m, d_cm, n_rep_ha) h_100(h_m, d_cm, n_rep_ha) # dominant height h100 for comparison h_q(h_m, d_cm) # quadratic mean height for comparison # if 20% of the trees are 100 stems/ha, Weise's dominant diameter and # d100 are equal d_cm <- rnorm(n = 500, mean = 35, sd = 7) dq_cm <- d_q(d_cm) h_m <- 0.8 * dq_cm * (d_cm / dq_cm)^0.8 # quick plausible height estim. h_dom_weise(h_m, d_cm, 1) h_100(h_m, d_cm, 1) # Weise's dominant diameter is greater than d100, if 20% of the trees # represent less than 100 trees/ha d_cm <- rnorm(n = 200, mean = 35, sd = 7) dq_cm <- d_q(d_cm) h_m <- 0.8 * dq_cm * (d_cm / dq_cm)^0.8 # quick plausible height estim. h_dom_weise(h_m, d_cm, 1) h_100(h_m, d_cm, 1) # Weise's dominant diameter is smaller than d100, if 20% of the trees # represent more than 100 trees/ha d_cm <- rnorm(n = 800, mean = 35, sd = 7) dq_cm <- d_q(d_cm) h_m <- 0.8 * dq_cm * (d_cm / dq_cm)^0.8 # quick plausible height estim. h_dom_weise(h_m, d_cm, 1) h_100(h_m, d_cm, 1) ``` ## See Also Other stand heights: `h_100()`, `h_q()`, `h_q_from_d_q()`

h_dom_weise function