R：用 0 随机替换数据帧的元素

我正在使用R编程语言.

假设我有以下数据框:

var_1 = var_2 = var_3 = var_4 = var_5 =  c("1,2,3,4,5,6,7,8,9,10")

my_data = data.frame(var_1,var_2,var_3,var_4,var_5)

my_data = rbind(my_data, my_data[rep(1, 100), ])

rownames(my_data) = 1:nrow(my_data)

数据如下所示:

    head(my_data)

                 var_1                var_2                var_3                var_4                var_5
1 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
2 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
3 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
4 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
5 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
6 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10

My Question:我想用0随机替换这个数据框中的元素——例如，最终结果应该是这样的(为简洁起见，我只显示第一行):

# desired result

                 var_1                var_2                var_3                var_4                var_5
1 1,0,3,0,5,6,0,0,9,10 1,2,0,4,5,0,0,8,9,0 1,0,3,0,0,0,0,8,9,0 1,2,3,4,0,6,7,0,0,10 1,2,0,4,5,0,7,8,0,10

我try 使用以下代码行(Replace random values in a column in a dataframe)来实现这一点:

my_data$var_1[sample(nrow(my_data),as.integer(0.5*nrow(my_data)) , replace = TRUE)] <- 0
my_data$var_2[sample(nrow(my_data),as.integer(0.5*nrow(my_data)), replace = TRUE)] <- 0
my_data$var_3[sample(nrow(my_data),as.integer(0.5*nrow(my_data)), replace = TRUE)] <- 0
my_data$var_4[sample(nrow(my_data),as.integer(0.5*nrow(my_data)), replace = TRUE)] <- 0
my_data$var_5[sample(nrow(my_data),as.integer(0.5*nrow(my_data)), replace = TRUE)] <- 0

但这是将一行中的所有元素替换为0(而不是仅替换一行中的一些元素):

head(my_data)
                 var_1                var_2                var_3                var_4                var_5
1 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10                    0                    0                    0
2                    0                    0 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10                    0
3                    0 1,2,3,4,5,6,7,8,9,10                    0 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
4                    0 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10                    0 1,2,3,4,5,6,7,8,9,10
5 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10
6 1,2,3,4,5,6,7,8,9,10                    0 1,2,3,4,5,6,7,8,9,10 1,2,3,4,5,6,7,8,9,10                    0

Can someone please show me what I am doing wrong and how to get the desired result?

谢谢