添加一列，按 R 中的组计算行数，直到第一个 1

Question

我有以下数据集：

test_df=data.frame(Group=c(1,1,1,1,2,2),var1=c(1,0,0,1,1,1),var2=c(0,0,1,1,0,0),var3=c(0,1,0,0,0,1))

Group	var1	var2	var3
1	1	0	0
1	0	0	1
1	0	1	0
1	1	1	0
2	1	0	0
2	1	0	1

我想为 var1-3 添加 3 列 (out1-3)，按组计算行数，直到第一个 1，

如下图：

Group	var1	var2	var3	out1	out2	out3
1	1	0	0	1	3	2
1	0	0	1	1	3	2
1	0	1	0	1	3	2
1	1	1	0	1	3	2
2	1	0	0	1	0	2
2	1	0	1	1	0	2

我使用了这个 R 代码，我对我的 3 个变量重复了它，而我的实际数据集包含的不仅仅是 3 列。但它不起作用：

test_var1<-select(test_df,Group,var1 )%>% 
  group_by(Group) %>% 
  mutate(out1 = row_number()) %>% 
  filter(var1 != 0) %>% 
  slice(1)

Answer 1

如果你只有 3 个“输出”变量，那么你可以创建如下三行

#1- Your dataset
df=data.frame(Group=rep(1,4),var1=c(1,0,0,1),var2=c(0,0,1,1),var3=c(0,1,0,0))

#2- Count the first row number with "1" value
df$out1=min(rownames(df)[which(df$var1==1)])
df$out2=min(rownames(df)[which(df$var2==1)])
df$out3=min(rownames(df)[which(df$var3==1)])

如果您有超过 3 列，那么最好创建一个循环，例如

for(i in 1:3){
    df[paste("out",i,sep="")]=min(rownames(df)[which(df[,which(colnames(df)==paste("var",i,sep=""))]==1)])
}

Answer 2

df <- data.frame(Group=c(1,1,1,1,2,2),
                 var1=c(1,0,0,1,1,1),
                 var2=c(0,0,1,1,0,0),
                 var3=c(0,1,0,0,0,1))

这适用于任意数量的变量，只要结构与示例中的相同（即组 + 许多 0 或 1 的变量）

df %>% 
  mutate(rownr = row_number()) %>%
  pivot_longer(-c(Group, rownr)) %>%
  group_by(Group, name) %>%
  mutate(out = cumsum(value != 1 & (cumsum(value) < 1)) + 1,
         out = ifelse(max(out) > n(), 0, max(out))) %>% 
  pivot_wider(names_from = c(name, name), values_from = c(value, out)) %>% 
  select(-rownr)

Returns:

  Group value_var1 value_var2 value_var3 out_var1 out_var2 out_var3
  <dbl>      <dbl>      <dbl>      <dbl>    <dbl>    <dbl>    <dbl>
1     1          1          0          0        1        3        2
2     1          0          0          1        1        3        2
3     1          0          1          0        1        3        2
4     1          1          1          0        1        3        2
5     2          1          0          0        1        0        2
6     2          1          0          1        1        0        2

添加一列，按 R 中的组计算行数，直到第一个 1

Add a column that count number of rows until the first 1, by group in R

r

data-management

dataframe