Design reference evapotranspiration (Design ETo)

Function to calculate the reference evapotranspitation for irrigation design.

Usage

design_eto(eto_daily_data, percentile = 0.8, grouping = NULL)

eto_daily_data: A data frame containing daily reference evapotranspiration values (mm day-1) named as "ETo", and other column with dates named "date". To estimate the design reference evapotranspiration, it is recommended to use more than 10 years of historical data.
percentile: The relative position of a value within the data distribution. The recomendation to desing irrigating is greater than 80 percent (0.8). For instance: The 90th (0.90) percentile of reference evapotranspiration (ETo) represents a value that is surpassed in only 10 percent of the observed period.
grouping: specifies the column used to group the data, typically by station. Use this parameter to calculate the design ETo separately for each station, based on the corresponding station code.

Returns a numeric object with the desing ETo for the respective data and percentile.

Roberto Filgueiras

if (FALSE) { # \dontrun{
design_eto_value <- design_eto(eto, percentile)
} # }