R 填写组内缺少的列

我收到一个EXCEL文件，如下所示:

structure(list(`Variable Name` = c("form.hhConsent", NA, NA, 
"form.hhReasonRefused", NA, NA, NA, "form.childrenRepeat.childrenGroup.childSex", 
NA, NA, "form.childrenRepeat.childrenGroup.dobSourceWho", NA, 
NA, NA, NA, "form.hohSex", NA, NA, "form.mothersRepeat.mothersGroup.spouseSex", 
NA, NA, "form.childrenRepeat.childrenGroup.treatmentConsent", 
NA, NA, NA, NA, "form.childrenRepeat.childrenGroup.noTreatReason", 
NA, NA, NA), Type = c(NA, "1", "0", NA, "1", "2", "99", NA, "1", 
"2", NA, "1", "2", "3", "99", NA, "1", "2", NA, "1", "2", NA, 
"1", "0", "2", "3", NA, "1", "2", "99"), Meaning = c(NA, "Yes", 
"No", NA, "No responsible could be found", "They don't want to", 
"Other reason", NA, "Male", "Female", NA, "Mother", "Father", 
"Neighbor", "Others", NA, "Male", "Female", NA, "Male", "Female", 
NA, "Yes", "No", "AMR grappe", "M54 grappe", NA, "allergy", "parent refusal", 
"other"), Missing_values = c(NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA), Format_values = c(NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA)), row.names = c(NA, -30L), class = "data.frame")

当前文件如下所示:

variable name   type      meaning
X1
                xxx         xxx
                xxx         xxx     
X2
                xxx.        xxx
                xxx         xxx
                xxx         xxx
x3
                xxx         xxx 

我想将其转换为常规数据集，如下所示:

variable name   type   meaning
x1               xxx.   xxx
x1               xxx.   xxx
x2               xxx    xxx
x2               xxx.   xxx
x2               xxx.   xxx
x3               xxx.   xxx

我的 idea 是:首先按"变量名"分组，然后补上缺失的变量名，最后一步是过滤掉类型和含义列中没有任何值的标题行.但这并不管用.问题是不存在可以为GROUP_BY的变量.

有没有人能帮我想一想怎么才能做到这一点？非常感谢~~！