# Anomalies relative to a climatology along selected dimension with or without cross-validation This function computes the anomalies relative to a climatology computed along the selected dimension (usually starting dates or forecast time) allowing the application or not of crossvalidated climatologies. The computation is carried out independently for experimental and observational data products. ```r CST_Anomaly( exp = NULL, obs = NULL, dim_anom = "sdate", cross = FALSE, memb_dim = "member", memb = TRUE, dat_dim = c("dataset", "member"), filter_span = NULL, ftime_dim = "ftime", ncores = NULL ) ``` ## Arguments - `exp`: An object of class `s2dv_cube` as returned by `CST_Start` function, containing the seasonal forecast experiment data in the element named `$data`. - `obs`: An object of class `s2dv_cube` as returned by `CST_Start` function, containing the observed data in the element named `$data`. - `dim_anom`: A character string indicating the name of the dimension along which the climatology will be computed. The default value is 'sdate'. - `cross`: A logical value indicating whether cross-validation should be applied or not. Default = FALSE. - `memb_dim`: A character string indicating the name of the member dimension. It must be one dimension in 'exp' and 'obs'. If there is no member dimension, set NULL. The default value is 'member'. - `memb`: A logical value indicating whether to subtract the climatology based on the individual members (TRUE) or the ensemble mean over all members (FALSE) when calculating the anomalies. The default value is TRUE. - `dat_dim`: A character vector indicating the name of the dataset and member dimensions. If there is no dataset dimension, it can be NULL. The default value is "c('dataset', 'member')". - `filter_span`: A numeric value indicating the degree of smoothing. This option is only available if parameter `cross` is set to FALSE. - `ftime_dim`: A character string indicating the name of the temporal dimension where the smoothing with 'filter_span' will be applied. It cannot be NULL if 'filter_span' is provided. The default value is 'ftime'. - `ncores`: An integer indicating the number of cores to use for parallel computation. The default value is NULL. It will be used only when 'filter_span' is not NULL. ## Returns A list with two S3 objects, 'exp' and 'obs', of the class 's2dv_cube', containing experimental and date-corresponding observational anomalies, respectively. These 's2dv_cube's can be ingested by other functions in CSTools. ## Examples ```r mod <- 1 : (2 * 3 * 4 * 5 * 6 * 7) dim(mod) <- c(dataset = 2, member = 3, sdate = 4, ftime = 5, lat = 6, lon = 7) obs <- 1 : (1 * 1 * 4 * 5 * 6 * 7) dim(obs) <- c(dataset = 1, member = 1, sdate = 4, ftime = 5, lat = 6, lon = 7) lon <- seq(0, 30, 5) lat <- seq(0, 25, 5) coords <- list(lon = lon, lat = lat) exp <- list(data = mod, coords = coords) obs <- list(data = obs, coords = coords) attr(exp, 'class') <- 's2dv_cube' attr(obs, 'class') <- 's2dv_cube' anom <- CST_Anomaly(exp = exp, obs = obs, cross = FALSE, memb = TRUE) ``` ## See Also `Ano_CrossValid`, `Clim` and `CST_Start` ## Author(s) Perez-Zanon Nuria, nuria.perez@bsc.es Pena Jesus, jesus.pena@bsc.es

CST_Anomaly function