在R中为指定列运行COUNTIF

我需要创建一个“新”列，并在指定列（即“输出”列）上运行与COUNTIF函数等效的函数。例如，我需要计算这些列是否包含3或4

右侧有所需列的示例数据

x  Output.1  Output.2  Output.3  Output.4  Output.5  y  new
1  3         3         NA        NA        NA        2  2
1  4         4         3         3         NA        2  4
1  3         3         3         3         3         2  5
1  2         2         4         4         4         2  3

我尝试过使用行和（经过一点搜索）例如：

df$new <- rowSums(df[c('Output.1', 'Output.2', 'Output.3', 'Output.4', 'Output.5')] == 3)

尽管后者对值求和，但我需要一个实例计数，并且我不知道如何在其中gt==3的条件

---

提前感谢

您可以为此使用

应用

：

df$new <- apply(df[, grep("Output.", names(df))], MARGIN = 1, 
                function(x) sum(x %in% c(3, 4), na.rm = T))

df 
#   x Output.1 Output.2 Output.3 Output.4 Output.5 y new
# 1 1        3        3       NA       NA       NA 2   2
# 2 1        4        4        3        3       NA 2   4
# 3 1        3        3        3        3        3 2   5
# 4 1        2        2        4        4        4 2   3

---

df$new Thank kath-这与该数据帧完美配合-当我在具有更多列的更大数据帧上使用它时，我会收到此错误-应用中的错误（Activity_final[，grep（“Output.”，names（Activity_final）），：dim（X）必须有正长度uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

到要使用的列。它返回

3 4 5 6 7 8 9 10 11

，因此不为空。在这种情况下，列在任何情况下都将始终是

“Output”

列。

df$new <- apply(df[, grep("Output.", names(df))], MARGIN = 1, 
                function(x) sum(x %in% c(3, 4), na.rm = T))

df 
#   x Output.1 Output.2 Output.3 Output.4 Output.5 y new
# 1 1        3        3       NA       NA       NA 2   2
# 2 1        4        4        3        3       NA 2   4
# 3 1        3        3        3        3        3 2   5
# 4 1        2        2        4        4        4 2   3