我今天碰到了一个奇怪的问题。原因可能是我不知道的基本问题，但我仍然很好奇这个问题可能会出现的原因以及可能解决的问题。
所以，想象一下，我们这里有一个像这样的数据框。
abc<-c("a","a","a","a","a","a","a","b","b","b","b","b","b","b","b","c","c","c",
"c","c","c","c","c","c","c","c","c","c","c","c")
count<-c(1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3)
xyz<-c("x","x","x","x","x","y","y","y","y","y","y","z","z","z","z","z","z",
"z","z","z","z","z","z","z","z","z","z","z","z","z")
total_df<-as.data.frame(cbind(abc,count,xyz))
正如您所看到的，我们在这里有3个变量和30个观测值。
如果您要将这些行发送到R，那么您将看到每个变量包含3个因子，因此变量都被分解：
total_df$abc
total_df$count
total_df$xyz
或者只是简单地检查一下：
class(total_df$abc)
class(total_df$count)
class(total_df$xyz)
现在，在下一步中，我想以这种方式调用其中一个变量：
total_df$count
偶然我意识到以下几行：
total_df$coun
total_df$cou
total_df$co
total_df$c
...所以这些行给出了与'total_df $ count'行完全相同的结果。这怎么可能？这种现象是否正常？我还没有创建一个名为'cou'的变量，R仍然可以识别它？！我在这忘了吗？它真的让我担心，因为这个问题可能会导致严重的头痛......有没有办法逃避/解决这个问题？我的意思是，告诉R只识别变量'count'？而且我不希望所有其他的 - 在我看来是'假的' - 像'coun'，'cou'这样的变量得到认可。
问题出现在另外两个主要变量'abc'和'xyz'中。
顺便说一下，我有2.12.0类型的R。
谢谢你，祝你有个愉快的一天 的Laszlo。