r - custom function with mutate do not work -

some custom functions not work in mutate. explain why calc2 , calc3 dont work, , how fix them work properly?

    library(dplyr)     m <- matrix(c(1,2,3,4,5,6,7,8,9), nrow = 3, byrow = t)              calc <- function(x1,x2,x3){ #scalar       return(x1 + x2 + x3)     }      calc2 <- function(x){ #vector       return(x[1] + x[2] + x[3])     }      calc3 <- function(x){ #list       x <- unlist(x)       return(sum(x))     }      as.data.frame(m) %>%        mutate(val  = calc(v1,v2,v3), #ok              val2 = calc2(c(v1,v2,v3) ), #ng              val3 = calc3(list(v1,v2,v3))) #ng 

below output:

    v1 v2 v3 val val2 val3     1  2  3   6   12   45     4  5  6  15   12   45     7  8  9  24   12   45 

we can without changing op's functions using rowwise

library(dplyr) as.data.frame(m) %>%          rowwise() %>%          mutate(val = calc(v1, v2, v3),                  val2 = calc2(c(v1, v2, v3)),                 val3 = calc3(list(v1, v2, v3))) # tibble: 3 × 6 #     v1    v2    v3   val  val2  val3 #  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #1     1     2     3     6     6     6 #2     4     5     6    15    15    15 #3     7     8     9    24    24    24