Missing values are denoted by a special value denoted by NA. However it is also possible for NA to be present as a character vector like this "NA". In the latter case, R does not know that this is actually a missing value. So this is problematic if you would like to find all missing values using a standard approach in R:
library(tidyhydat)
library(dplyr)
#>
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#>
#> filter, lag
#> The following objects are masked from 'package:base':
#>
#> intersect, setdiff, setequal, union
hy_stations() %>%
filter(is.na(SED_STATUS))
#> Queried from version of HYDAT released on 2019-07-17
#> Observations: 0
#> Jurisdictions:
#> Station(s) returned: 0
#> Stations requested but not returned:
#> All stations returned.
#> # A tibble: 0 x 15
#> # ... with 15 variables: STATION_NUMBER <chr>, STATION_NAME <chr>,
#> # PROV_TERR_STATE_LOC <chr>, REGIONAL_OFFICE_ID <dbl>, HYD_STATUS <chr>,
#> # SED_STATUS <chr>, LATITUDE <dbl>, LONGITUDE <dbl>,
#> # DRAINAGE_AREA_GROSS <dbl>, DRAINAGE_AREA_EFFECT <dbl>, RHBN <lgl>,
#> # REAL_TIME <lgl>, CONTRIBUTOR_ID <int>, OPERATOR_ID <int>,
#> # DATUM_ID <int>
To fix this issue one would need to go into the source code for hy_stations and define the NA's to be true missing values. The issue in the tidyhydat repo is here: https://github.com/ropensci/tidyhydat/issues/125
Missing values are denoted by a special value denoted by
NA. However it is also possible for NA to be present as a character vector like this"NA". In the latter case, R does not know that this is actually a missing value. So this is problematic if you would like to find all missing values using a standard approach in R:To fix this issue one would need to go into the source code for
hy_stationsand define the NA's to be true missing values. The issue in the tidyhydat repo is here: https://github.com/ropensci/tidyhydat/issues/125