# Calculating quantiles from distribution parameters Calculates quantiles from distribution parameters received by parameters or from a named vector. ```r quantiles(x, p, distr = attr(x, "distribution")) ``` ## Arguments - `x`: object returned by parameters or a named vector. In the latter you have to specify the `distr`-argument. - `p`: numeric vector giving the quantiles to calculate. - `distr`: character object defining the distribution. Supported types are "gev", "gum" and "gpd". You do not need to set this, if `x` is from parameters. ## Returns numeric vector, matrix, list, or data.frame of the quantiles and with class `quantiles`. The object contains the following attributes: * `distribution`: a character indicating the used distribution * `p`: a vector with the calculated quantiles * `source`: a list with background information (used function, data, n, formula, trimmings; mainly for internal purposes) The attributes are hidden in the print-function for a clearer presentation. ## Examples ```r # Generating data sets: xmat <- matrix(rnorm(100), nc = 4) xvec <- xmat[, 3] xlist <- lapply(1L:ncol(xmat), function(i) xmat[, i]) xdat <- data.frame( station = rep(letters[1:2], each = 50), season = rep(c("S", "W"), 50), hq = as.vector(xmat) ) # Calculating quantiles from parameters-object tlm <- TLMoments(xvec, leftrim = 0, rightrim = 1) quantiles(parameters(tlm, "gev"), c(.9, .99)) tlm <- TLMoments(xmat, leftrim = 1, rightrim = 1) quantiles(parameters(tlm, "gum"), c(.9, .95, .999)) tlm <- TLMoments(xlist) quantiles(parameters(tlm, "gpd"), .999) tlm <- TLMoments(xdat, hq ~ station, leftrim = 2, rightrim = 3) quantiles(parameters(tlm, "gev"), seq(.1, .9, .1)) tlm <- TLMoments(xdat, hq ~ station + season, leftrim = 0, rightrim = 2) quantiles(parameters(tlm, "gum"), seq(.1, .9, .1)) # Distribution can be overwritten (but parameters have to fit) tlm <- TLMoments(xvec, leftrim = 0, rightrim = 1) params <- parameters(tlm, "gev") quantiles(params, c(.9, .99)) quantiles(params[1:2], c(.9, .99), distr = "gum") evd::qgumbel(c(.9, .99), loc = params[1], scale = params[2]) # Using magrittr library(magrittr) rgev(50, shape = .3) %>% TLMoments(leftrim = 0, rightrim = 1) %>% parameters("gev") %>% quantiles(c(.99, .999)) # Calculating quantiles to given parameters for arbitrary functions quantiles(c(mean = 10, sd = 3), c(.95, .99), "norm") qnorm(c(.95, .99), mean = 10, sd = 3) # These give errors: #quantiles(c(loc = 10, scale = 5, shape = .3), c(.95, .99), "notexistingdistribution") #quantiles(c(loc = 10, scale = 5, shpe = .3), c(.95, .99), "gev") # wrong arguments ``` ## See Also `PWMs`, `TLMoments`, `parameters`, `summary.quantiles`

quantiles function