處理來港

Question

我有一個數據幀dt：

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"2015-11-30 06:00:00", "2015-11-30 12:00:00", "2015-11-30 18:00:00" 
), class = "factor")), .Names = c("datetime", "precip", "bin" 
), row.names = c(NA, 30L), class = "data.frame") 

的意圖是通過bin聚集dt$precip並返回NAs其中dt$precip擁有所有NAs在bin和忽略NAs在其中的價值觀和NAs並存完事。我試過了：

tri <- aggregate(dt$precip, list(dt$bin), FUN=sum, na.rm=T) 

tri 
       Group.1 x 
1 2015-04-01 00:00:00 0.3 
2 2015-04-01 06:00:00 3.1 
3 2015-04-01 12:00:00 2.2 
4 2015-04-01 18:00:00 0.0 
5 2015-04-02 00:00:00 0.0 

總和和刪除/忽略前三個箱子中的NA是正確的。但是，它將zeros插入最後兩個倉中，而不是NAs。我需要NAs。

我曾嘗試：

tri <- aggregate(dt$precip, list(dt$bin), FUN=sum, na.rm=TRUE, na.action=na.omit) 

Error in FUN(X[[1L]], ...) : invalid 'type' (closure) of argument 

和

tri <- aggregate(dt$precip, list(dt$bin), function(x) sum(x, na.rm=TRUE), na.action = na.pass) 

Error in FUN(X[[1L]], ...) : 
    unused argument (na.action = function (object, ...) 
object) 

tri <- aggregate(dt$precip, list(dt$bin), FUN=sum, na.rm=TRUE, na.action="na.pass") 

Error in FUN(X[[1L]], ...) : invalid 'type' (character) of argument 

任何事情，我在這裏失蹤？我有> 20,000個文件，並且我的整個代碼都集中在aggregate函數中。我知道其他方法使用dplyr和data.table等存在，但我會明白一個解決方案，使用aggregate尤其是在list對象。

Answer 1

時all在「雨」特定「本」的元素是NA或else與na.rm=TRUE

aggregate(precip~bin, dt,FUN = function(x) 
     if(all(is.na(x))) NA else sum(x, na.rm=TRUE), na.action=na.pass) 
#      bin precip 
#1 2015-04-01 00:00:00 0.3 
#2 2015-04-01 06:00:00 3.1 
#3 2015-04-01 12:00:00 2.2 
#4 2015-04-01 18:00:00  NA 
#5 2015-04-02 00:00:00  NA