R删除索引中的nrow小于特定值的数据帧中的行(R delete rows in data frame where nrow of index is smaller than certain valu

R删除索引中的nrow小于特定值的数据帧中的行(R delete rows in data frame where nrow of index is smaller than certain value)

当具有相同索引的行数小于预先指定的值时，我想删除数据框中的某些行。

> fof.6.5[1:15, 1:3] draw Fund.ID Firm.ID 1 1 1667 666 2 1 1572 622 3 1 1392 553 4 1 248 80 5 1 3223 332 6 2 2959 1998 7 2 2659 1561 8 2 14233 2517 9 2 10521 12579 10 2 3742 1045 11 3 9093 10121 12 3 15681 21626 13 3 26371 70170 14 4 27633 52720 15 4 13751 656

在这个例子中，我希望每个索引有5行。 第三次抽奖（这是我的索引）少于5行。 如果抽奖少于5行，我如何删除第三个抽奖？

I want to delete certain rows in a data frame when the number of rows with the same index is smaller than a pre-specified value.

> fof.6.5[1:15, 1:3] draw Fund.ID Firm.ID 1 1 1667 666 2 1 1572 622 3 1 1392 553 4 1 248 80 5 1 3223 332 6 2 2959 1998 7 2 2659 1561 8 2 14233 2517 9 2 10521 12579 10 2 3742 1045 11 3 9093 10121 12 3 15681 21626 13 3 26371 70170 14 4 27633 52720 15 4 13751 656

In this example, I want each index to have 5 rows. The third draw (which is my index) has fewer than 5 rows. How can I delete the draws like the third one if they have fewer than 5 rows?

最满意答案

您可以使用dplyr执行此操作（假设您的数据位于名为dt的数据框中：

dt %>% group_by(draw) %>% filter(n() >= 5) %>% ungroup()

或者你可以使用table或xtabs ：

tab <- xtabs(~ draw, dt) dt[!dt$draw %in% as.numeric(names(which(tab < 5))), ]

You could do this using dplyr (assuming your data is in a data frame called dt:

dt %>% group_by(draw) %>% filter(n() >= 5) %>% ungroup()

Or you could use table or xtabs:

tab <- xtabs(~ draw, dt) dt[!dt$draw %in% as.numeric(names(which(tab < 5))), ]