我对r很新（而且很累 - 我想我的大脑目前还没有正常工作）但是对我来说下面的代码应该只返回10行 - 它返回66.为什么会这样？
library(dplyr)
a <- structure(list(calls_in_range = c(17, 14, 6, 4, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1), mid_point = c(-20680,
-20660, -20640, -20700, -36900, -36500, -36380, -36020, -35960,
-35260, -35140, -34640, -33060, -32600, -30920, -29340, -29100,
-28780, -27980, -27640, -27220, -27160, -26980, -26800, -26740,
-26500, -25640, -25540, -24840, -24820, -24800, -24380, -23880,
-23820, -23720, -23320, -22220, -21920, -21860, -21760, -21060,
-20240, -19780, -18700, -18500, -17500, -16740, -16500, -14260,
-14200, -14120, -13860, -13420, -13120, -12780, -12740, -12460,
-12420, -12280, -12260, -11720, -10660, -10060, -9960, -6380,
-5520), lower_range = c(-20690, -20670, -20650, -20710, -36910,
-36510, -36390, -36030, -35970, -35270, -35150, -34650, -33070,
-32610, -30930, -29350, -29110, -28790, -27990, -27650, -27230,
-27170, -26990, -26810, -26750, -26510, -25650, -25550, -24850,
-24830, -24810, -24390, -23890, -23830, -23730, -23330, -22230,
-21930, -21870, -21770, -21070, -20250, -19790, -18710, -18510,
-17510, -16750, -16510, -14270, -14210, -14130, -13870, -13430,
-13130, -12790, -12750, -12470, -12430, -12290, -12270, -11730,
-10670, -10070, -9970, -6390, -5530), upper_range = c(-20670,
-20650, -20630, -20690, -36890, -36490, -36370, -36010, -35950,
-35250, -35130, -34630, -33050, -32590, -30910, -29330, -29090,
-28770, -27970, -27630, -27210, -27150, -26970, -26790, -26730,
-26490, -25630, -25530, -24830, -24810, -24790, -24370, -23870,
-23810, -23710, -23310, -22210, -21910, -21850, -21750, -21050,
-20230, -19770, -18690, -18490, -17490, -16730, -16490, -14250,
-14190, -14110, -13850, -13410, -13110, -12770, -12730, -12450,
-12410, -12270, -12250, -11710, -10650, -10050, -9950, -6370,
-5510)), class = "data.frame", row.names = c(NA, -66L), .Names = c("calls_in_range",
"mid_point", "lower_range", "upper_range"))
top_n(a, 10, calls_in_range)
答案 0 :(得分：8)
如果您检查calls_in_range列，则可以看到存在关系。这是用于订购的变量。根据{{3}} n函数中的top_n参数：
要返回的行数。如果x被分组，则这是每组的行数。 如果有联系，将包含多于n行。如果n为正，则选择前n行。如果为负数，则选择底部的n行。
这就是它返回的行多于预期的原因。