CST_PeriodMean {CSIndicators}

Period Mean on 's2dv_cube' objects

Description

Period Mean computes the average (mean) of a given variable in a period. Providing temperature data, two agriculture indices can be obtained by using this function:

• 'GST', Growing Season average Temperature: The average temperature from April 1st to Octobe 31st.

• 'SprTX', Spring Average Maximum Temperature: The average daily maximum temperature from April 1st to May 31st.

Usage

CST_PeriodMean(
  data,
  start = NULL,
  end = NULL,
  time_dim = "time",
  na.rm = FALSE,
  ncores = NULL
)

Arguments

data

An 's2dv_cube' object as provided function CST_Start or CST_Load in package CSTools.

start

An optional parameter to defined the initial date of the period to select from the data by providing a list of two elements: the initial date of the period and the initial month of the period. By default it is set to NULL and the indicator is computed using all the data provided in data.

end

An optional parameter to defined the final date of the period to select from the data by providing a list of two elements: the final day of the period and the final month of the period. By default it is set to NULL and the indicator is computed using all the data provided in data.

time_dim

A character string indicating the name of the dimension to compute the indicator. By default, it is set to 'time'. More than one dimension name matching the dimensions provided in the object data$data can be specified.

na.rm

A logical value indicating whether to ignore NA values (TRUE) or not (FALSE).

ncores

An integer indicating the number of cores to use in parallel computation.

Value

An 's2dv_cube' object containing the indicator in the element data with dimensions of the input parameter 'data' except the dimension where the mean has been computed (specified with 'time_dim'). The 'Dates' array is updated to the dates corresponding to the beginning of the aggregated time period. A new element called 'time_bounds' will be added into the 'attrs' element in the 's2dv_cube' object. It consists of a list containing two elements, the start and end dates of the aggregated period with the same dimensions of 'Dates' element.

Examples

exp <- NULL
exp$data <- array(rnorm(45), dim = c(member = 7, sdate = 4, time = 3))
Dates <- c(seq(as.Date("2000-11-01", "%Y-%m-%d", tz = "UTC"), 
              as.Date("2001-01-01", "%Y-%m-%d", tz = "UTC"), by = "month"),
          seq(as.Date("2001-11-01", "%Y-%m-%d", tz = "UTC"), 
              as.Date("2002-01-01", "%Y-%m-%d", tz = "UTC"), by = "month"),
          seq(as.Date("2002-11-01", "%Y-%m-%d", tz = "UTC"), 
              as.Date("2003-01-01", "%Y-%m-%d", tz = "UTC"), by = "month"),
          seq(as.Date("2003-11-01", "%Y-%m-%d", tz = "UTC"), 
              as.Date("2004-01-01", "%Y-%m-%d", tz = "UTC"), by = "month"))
dim(Dates) <- c(sdate = 4, time = 3)
exp$attrs$Dates <- Dates
class(exp) <- 's2dv_cube'

SA <- CST_PeriodMean(exp, start = list(01, 12), end = list(01, 01))