How to calculate the mean (and median) of rows

[sdeepj]

I'm trying to create two new columns in a data frame, where one is the mean of each row and the median of each row. I tried using the rowMeans()function, but I get an error message.

what I have

  n  x  z
A 43  5 9
B 23 33 7
C 8   4 67
D 95 13 43
type or paste code here

what I want

  n   x  z avg med
A 43  5  9 19  9
B 23 33  7 21 23
C  8  4 67 26  8
D 95 13 43 50 43
type or paste code here

[technocrat]

a <- readr::read_csv("/Users/ro/Desktop/grist.csv")
#> Rows: 4 Columns: 4
#> ── Column specification ────────────────────────────────────────────────────────
#> Delimiter: ","
#> chr (1): id
#> dbl (3): n, x, z
#> 
#> ℹ Use `spec()` to retrieve the full column specification for this data.
#> ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
a
#> # A tibble: 4 × 4
#>   id        n     x     z
#>   <chr> <dbl> <dbl> <dbl>
#> 1 A        43     5     9
#> 2 B        23    33     7
#> 3 C         8     4    67
#> 4 D        95    13    43
# save out and remove id column to create all numeric
id <- a[1]
a <- a[-1]
a$means <- rowMeans(a)
a$medians <- apply(a[,1:3],1,median)
a <- cbind(id,a)
a
#>   id  n  x  z    means medians
#> 1  A 43  5  9 19.00000       9
#> 2  B 23 33  7 21.00000      23
#> 3  C  8  4 67 26.33333       8
#> 4  D 95 13 43 50.33333      43

^{Created on 2022-12-22 with reprex v2.0.2}