peek at the results in a dplyr pipeline

peek(df, n = 5, message = NULL)

Arguments

df	dataframe in pipeline
n	number of rows to show
message	give a message along with peeking at the data

Details

A wrapper around giving a head and tail command but only as a side effect so the original data frame is passed along to continue on for furthermanipulation in the pipeline

Examples

library(dplyr)
Theoph %>% select(Subject, Time, conc) %>% peek %>% group_by(Subject) %>%
summarize(cmax = max(conc))
#> Taking a peek...
#>   Subject Time  conc
#> 1       1 0.00  0.74
#> 2       1 0.25  2.84
#> 3       1 0.57  6.57
#> 4       1 1.12 10.50
#> 5       1 2.02  9.66
#> ...................
#>     Subject  Time conc
#> 128      12  5.07 8.57
#> 129      12  7.07 6.59
#> 130      12  9.03 6.11
#> 131      12 12.05 4.57
#> 132      12 24.15 1.17
#> `summarise()` ungrouping output (override with `.groups` argument)
#> # A tibble: 12 x 2
#>    Subject  cmax
#>    <ord>   <dbl>
#>  1 6        6.44
#>  2 7        7.09
#>  3 8        7.56
#>  4 11       8   
#>  5 3        8.2 
#>  6 2        8.33
#>  7 4        8.6 
#>  8 9        9.03
#>  9 12       9.75
#> 10 10      10.2 
#> 11 1       10.5 
#> 12 5       11.4 

Theoph %>% select(Subject, Time, conc) %>% peek(message = "after select") %>%
 group_by(Subject) %>%
summarize(cmax = max(conc))
#> after select
#>   Subject Time  conc
#> 1       1 0.00  0.74
#> 2       1 0.25  2.84
#> 3       1 0.57  6.57
#> 4       1 1.12 10.50
#> 5       1 2.02  9.66
#> ...................
#>     Subject  Time conc
#> 128      12  5.07 8.57
#> 129      12  7.07 6.59
#> 130      12  9.03 6.11
#> 131      12 12.05 4.57
#> 132      12 24.15 1.17
#> `summarise()` ungrouping output (override with `.groups` argument)
#> # A tibble: 12 x 2
#>    Subject  cmax
#>    <ord>   <dbl>
#>  1 6        6.44
#>  2 7        7.09
#>  3 8        7.56
#>  4 11       8   
#>  5 3        8.2 
#>  6 2        8.33
#>  7 4        8.6 
#>  8 9        9.03
#>  9 12       9.75
#> 10 10      10.2 
#> 11 1       10.5 
#> 12 5       11.4 

# nice for saving full objects but still seeing their output
cmax_theoph <- Theoph %>% select(Subject, Time, conc) %>%
peek(message = "after select") %>%
 group_by(Subject) %>%
summarize(cmax = max(conc)) %>% peek
#> after select
#>   Subject Time  conc
#> 1       1 0.00  0.74
#> 2       1 0.25  2.84
#> 3       1 0.57  6.57
#> 4       1 1.12 10.50
#> 5       1 2.02  9.66
#> ...................
#>     Subject  Time conc
#> 128      12  5.07 8.57
#> 129      12  7.07 6.59
#> 130      12  9.03 6.11
#> 131      12 12.05 4.57
#> 132      12 24.15 1.17
#> `summarise()` ungrouping output (override with `.groups` argument)
#> Taking a peek...
#> # A tibble: 5 x 2
#>   Subject  cmax
#>   <ord>   <dbl>
#> 1 6        6.44
#> 2 7        7.09
#> 3 8        7.56
#> 4 11       8   
#> 5 3        8.2 
#> ...................
#> # A tibble: 5 x 2
#>   Subject  cmax
#>   <ord>   <dbl>
#> 1 9        9.03
#> 2 12       9.75
#> 3 10      10.2 
#> 4 1       10.5 
#> 5 5       11.4 
cmax_theoph # still saves full output
#> # A tibble: 12 x 2
#>    Subject  cmax
#>    <ord>   <dbl>
#>  1 6        6.44
#>  2 7        7.09
#>  3 8        7.56
#>  4 11       8   
#>  5 3        8.2 
#>  6 2        8.33
#>  7 4        8.6 
#>  8 9        9.03
#>  9 12       9.75
#> 10 10      10.2 
#> 11 1       10.5 
#> 12 5       11.4