使用R中的cat删除最后一个向量元素中的逗号

Question

我在R中面临一个小问题，但我不知道如何解决它。

我想使用cat在sep中使用cat参数在R控制台中打印消息。这是我尝试过的：

words <- c("foo", "foo2", "foo3")
cat("words not included:", "\n", words, sep = ",")
#words not included:,
#,foo,foo2,foo3

我们可以看到逗号插入在:之后和foo之前。

然后我做了：

cat("words not included:", "\n", words, sep = ",", "\n")
#words not included:,
#,foo,foo2,foo3,

我想要的输出是：

#words not included:
    #foo,foo2,foo3

Answer 1

只需在此处将paste与collapse一起使用：

words <- c("foo", "foo2", "foo3")
paste("words not included:", "\n", paste(words, collapse=","))

[1] "words not included: \n foo,foo2,foo3"

Answer 2

您可以使用toString()代替sep中的cat()参数。

cat("words not included:", "\n", toString(words),  "\n")

words not included: 
 foo, foo2, foo3