add missed value based on the value of the column in r

Question

This is my sample dataset:

   vector1 <-
      data.frame(
        \"name\" = \"a\",
        \"age\" = 10,
        \"fruit\" = c(\"orange\", \"cherry\", \"app         


        

Answer 1

A solution using dplyr and tidyr. We can use complete to expand the data frame and specify the fill values as 0 to count.

Notice that I changed your list name from list to fruit_list because it is a bad practice to use reserved words in R to name an object. Also notice that when I created the example data frame I set stringsAsFactors = FALSE because I don't want to create factor columns. Finally, I used lapply instead of for-loop to loop through the list elements.

library(dplyr)
library(tidyr)

fruit_list2 <- lapply(fruit_list, function(x){
  x2 <- x %>%
    complete(name, age, fruit = default, tag = c(1, 2), fill = list(count = 0)) %>%
    select(name, age, fruit, count, tag) %>%
    arrange(tag, fruit) %>%
    as.data.frame()
  return(x2)
})

fruit_list2
# [[1]]
#   name age  fruit count tag
# 1    a  10  apple     0   1
# 2    a  10 cherry     1   1
# 3    a  10  mango     0   1
# 4    a  10 orange     1   1
# 5    a  10  apple     1   2
# 6    a  10 cherry     0   2
# 7    a  10  mango     0   2
# 8    a  10 orange     0   2
# 
# [[2]]
#   name age  fruit count tag
# 1    b  33  apple     0   1
# 2    b  33 cherry     0   1
# 3    b  33  mango     0   1
# 4    b  33 orange     0   1
# 5    b  33  apple     1   2
# 6    b  33 cherry     0   2
# 7    b  33  mango     1   2
# 8    b  33 orange     0   2
# 
# [[3]]
#   name age  fruit count tag
# 1    c  58  apple     1   1
# 2    c  58 cherry     1   1
# 3    c  58  mango     0   1
# 4    c  58 orange     0   1
# 5    c  58  apple     0   2
# 6    c  58 cherry     0   2
# 7    c  58  mango     0   2
# 8    c  58 orange     0   2

DATA

vector1 <-
  data.frame(
    "name" = "a",
    "age" = 10,
    "fruit" = c("orange", "cherry", "apple"),
    "count" = c(1, 1, 1),
    "tag" = c(1, 1, 2),
    stringsAsFactors = FALSE
  )
vector2 <-
  data.frame(
    "name" = "b",
    "age" = 33,
    "fruit" = c("apple", "mango"),
    "count" = c(1, 1),
    "tag" = c(2, 2),
    stringsAsFactors = FALSE
  )
vector3 <-
  data.frame(
    "name" = "c",
    "age" = 58,
    "fruit" = c("cherry", "apple"),
    "count" = c(1, 1),
    "tag" = c(1, 1),
    stringsAsFactors = FALSE
  )

fruit_list <- list(vector1, vector2, vector3)

default <- c("cherry", "orange", "apple", "mango")