R/get_winfapapi.R
get_amax.RdThe function queries the NRFA API for the .AM file similar to the WINFAP file for a given stations. It then processes the file in a fashion similar to read_amax.
get_amax(station)a data.frame with information on the annual maxima for the station with the following columns
NRFA station number (can be a vector of station numbers)
the correct water year for the peak flow
date of maximum flow
the maximum flow in m3/s
the stage (height) reached by the river - this information is used to derive the flow via a rating curve
logical, if TRUE the water year has been flagged as rejected by the NRFA
read_amax. Information on river flow gauging in the UK and the annual maxima can be found at the National River Flow Archive website https://nrfa.ceh.ac.uk
a40003 <- get_amax(40003) # the Medway at Teston / East Farleigh
multipleStations <- get_amax(c(40003, 42003))
names(multipleStations)
#> [1] "40003" "42003"
summary(multipleStations$`42003`)
#> Station WaterYear Date Flow
#> Min. :42003 Min. :1975 Min. :1976-09-30 21:00:00 Min. : 4.16
#> 1st Qu.:42003 1st Qu.:1987 1st Qu.:1987-11-12 05:00:00 1st Qu.:15.71
#> Median :42003 Median :1999 Median :1999-12-25 02:15:00 Median :21.00
#> Mean :42003 Mean :1999 Mean :2000-01-16 14:34:17 Mean :25.05
#> 3rd Qu.:42003 3rd Qu.:2011 3rd Qu.:2012-06-12 06:45:00 3rd Qu.:29.40
#> Max. :42003 Max. :2023 Max. :2023-11-02 10:45:00 Max. :81.18
#> Stage Rejected
#> Min. :-9999.000 Mode :logical
#> 1st Qu.: 1.241 FALSE:29
#> Median : 1.383 TRUE :20
#> Mean :-1427.148
#> 3rd Qu.: 1.621
#> Max. : 2.134