R 如何根据数据顺序排列列联表？

给定

然后

unique按向量的出现顺序返回向量的唯一元素。通过按所需顺序提取表元素，可以像任何其他结构一样对表进行排序。因此，如果将unique的输出传递给[，]，那么将按照向量的出现顺序对表进行排序

   MALE  FEMALE
B  5     5
A  5     10
X  10    12

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如果您根据所需的顺序排列因子级别，您将获得所需的结果

tab <- table(res$Group, res$ss)[unique(res$Group),]

资料

考虑RE[]

   MALE  FEMALE
B  5     5
A  5     10
X  10    12

tab <- table(res$Group, res$ss)[unique(res$Group),]

res$Group <- factor(res$Group, levels = c('B', 'A', 'X'))
#If it is based on occurrence in Group column we can use 
#res$Group <- factor(res$Group, levels = unique(res$Group))
table(res$Group, res$ss)
#Or just
#table(res)

#    female male
#  B      1    2
#  A      1    1
#  X      0    1

res <- structure(list(Group = structure(c(2L, 2L, 2L, 1L, 1L, 3L), 
.Label = c("A", "B", "X"), class = "factor"), ss = structure(c(2L, 2L, 1L, 2L, 
1L, 2L), .Label = c("female", "male"), class = "factor")), 
class = "data.frame", row.names = c(NA, -6L))