R中具有数据帧的每一行的最小值和最大值

问题描述

我需要计算几个参加在线考试的人的处理时间。因此，每个人都有很多时间戳（每个任务一个时间戳）。根据最小日期值和最大日期值之间的时间差计算处理的持续时间。以下示例有效（student_1），但仅在没有值丢失（student_2和student_3）时有效。有什么想法吗？

library(anytime)

number <- c(1,2,3)
uniquename <- c("student_1","student_2","student_3")
timestamp_1 <- c(anytime("2020-02-25T12:42:56.476Z"),NA,anytime("2020-02-25T10:05:22.388Z"))
timestamp_2 <- c(anytime("2020-02-25T12:51:22.388Z"),anytime("2020-02-25T12:51:22.388Z"),NA)
timestamp_3 <- c(anytime("2020-02-25T13:00:45.042Z"),anytime("2020-02-25T13:00:45.042Z"),NA)
timestamp_4 <- c(anytime("2020-02-25T13:31:48.073Z"),anytime("2020-02-25T13:31:48.073Z"),NA)
timestamp_5 <- c(anytime("2020-02-25T14:22:57.103Z"),anytime("2020-02-25T15:00:00Z"),anytime("2020-02-25T14:05:00Z"))

df3 <- data.frame(number,uniquename,timestamp_1,timestamp_2,timestamp_3,timestamp_4,timestamp_5)

df3$date_min <- apply(df3[3:7],1,FUN=min)
df3$date_max <- apply(df3[3:7],FUN=max)

df3$date_min <- anytime(df3$date_min)
df3$date_max <- anytime(df3$date_max)

df3$diff <- difftime(df3$date_min,df3$date_max,units = "mins")
df3$diff <- round(df3$diff,0)
df3$diff <- as.numeric(df3$diff)*(-1)

View(df3)

解决方法

这是一种java.lang.NullPointerException [EDT] 0:0:0,873 - Exception: java.lang.NullPointerException - null at com.codename1.ui.Container.insertComponentAtImpl(Container.java:926) at com.codename1.ui.Container.insertComponentAt(Container.java:918) at com.codename1.ui.Container.addComponent(Container.java:855) at com.codename1.ui.BrowserComponent$9.run(BrowserComponent.java:534) at com.codename1.ui.Display.processSerialCalls(Display.java:1331) at com.codename1.ui.Display.edtLoopImpl(Display.java:1274) at com.codename1.ui.Display.mainEDTLoop(Display.java:1162) at com.codename1.ui.RunnableWrapper.run(RunnableWrapper.java:120) at com.codename1.impl.CodenameOneThread.run(CodenameOneThread.java:176) 方法

data.table

,

据我所知，您可以使用当前方法为function ID = local_isfunction(FUNNAME) try nargin(FUNNAME) ; % nargin errors when FUNNAME is not a function ID = 1 + isa(FUNNAME,'function_handle') ; % 1 for m-file,2 for handle catch ME % catch the error of nargin switch (ME.identifier) case 'MATLAB:nargin:isScript' ID = -1 ; % script case 'MATLAB:narginout:notValidMfile' ID = -2 ; % probably another type of file,or it does not exist case 'MATLAB:narginout:functionDoesnotExist' ID = -3 ; % probably a handle,but not to a function case 'MATLAB:narginout:BadInput' ID = -4 ; % probably a variable or an array otherwise ID = 0 ; % unknown cause for error end end 和na.rm添加min()参数：

max()