I find solutions when the data_frame is grouped, but none when it's not.
The data: # A tibble: 813,693 × 9 site_nbr year mon day hr min tz cfs sampdt <chr> <int> <int> <int> <dbl> <dbl> <chr> <dbl> <dttm> 1 14211720 1988 10 1 0 10 PDT 16800 1988-10-01 00:10:00 2 14211720 1988 10 1 0 20 PDT 16800 1988-10-01 00:20:00 3 14211720 1988 10 1 0 30 PDT 17300 1988-10-01 00:30:00 4 14211720 1988 10 1 0 40 PDT 18200 1988-10-01 00:40:00 5 14211720 1988 10 1 0 50 PDT 18100 1988-10-01 00:50:00 6 14211720 1988 10 1 1 0 PDT 18400 1988-10-01 01:00:00 7 14211720 1988 10 1 1 10 PDT 18700 1988-10-01 01:10:00 8 14211720 1988 10 1 1 20 PDT 19200 1988-10-01 01:20:00 9 14211720 1988 10 1 1 30 PDT 19200 1988-10-01 01:30:00 10 14211720 1988 10 1 1 40 PDT 18900 1988-10-01 01:40:00 # … with 813,683 more rows The script: library(tidyverse) max_pdx_disc <- pdx_disc %>% summarize(max_cfs = max(cfs), max_cfs_sampdt = cfs(which.max(cfs))) The error:
source('../scripts/filter_by_column_max.r')
Error: Problem with `summarise()` column `max_cfs_sampdt`. `max_cfs_sampdt = sampt(which.max(cfs))`. could not find function "sampt"
Run `rlang::last_error()` to see where the error occurred.
I looked at the the last_error and the traceback without understanding how to filter the row with the maximum cfs value. What do I read to learn how to return this row? TIA, Rich ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.