filter_all(.tbl, .vars_predicate)

filter_if(.tbl, .predicate, .vars_predicate)

filter_at(.tbl, .vars, .vars_predicate)

https://www.rdocumentation.org/packages/dplyr/versions/0.7.8/topics/filter_all

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Useful functions

    Center: mean(), median()

    Spread: sd(), IQR(), mad()

    Range: min(), max(), quantile()

    Position: first(), last(), nth(),

    Count: n(), n_distinct()

    Logical: any(), all()

https://www.rdocumentation.org/packages/dplyr/versions/0.7.8/topics/summarise

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group_map(.data, .f, ..., .keep = FALSE)

group_modify(.data, .f, ..., .keep = FALSE)

group_walk(.data, .f, ...)

https://dplyr.tidyverse.org/reference/group_map.html#see-also