Question

我有一个相当简单的动物遭遇历史数据集

Encounter history data - Shows each date data was collected and every animal that was seen during each encounter

我正在尝试运行一个函数，该函数将使用tapply代码显示每个动物的最早日期;

disco1<-tapply(dataSc$Date,dataSc$Final.ID,min)

然而，它给了我以下错误;

Summary.factor中的错误（c（62L，72L，2L，63L，33L，59L，78L，39L），na.rm = FALSE）： 'min'对因素没有意义

我不确定为什么它不起作用，因为我的主管对类似的数据集使用了相同的代码。任何帮助都会很棒：）

结构（清单（年份= c）（2009L，2009L，2011L，2011L，2011L，2011L ），日期=结构（c（48L，4L，60L，64L，16L，22L）,.标签= c（＆＃34; 01/06 / 2012＆＃34;，＆＃34; 01/08/2011＆＃34;，＆＃34; 02/01 / 2014＆＃34;，＆＃34; 02/03/2009＆＃34;，＆＃34; 03/03/2009＆＃34 ;，＆＃34; 03/06 / 2015＆＃34;，＆＃34; 03/09/2011＆＃34;，＆＃34; 04/03 / 2015＆＃34;，＆＃34; 04/04 / 2015＆＃34;，＆＃34; 04/07 / 2012＆＃34 ;，＆＃34; 04/08/2012＆＃34;，＆＃34; 04/08/2015＆＃34;，＆＃34; 05/03/2009＆＃34;，＆＃34; 05/07/2011＆＃34;，＆＃34; 05/08/2015＆＃34 ;，＆＃34; 06/07/2011＆＃34;，＆＃34; 06/08/2015＆＃34;，＆＃34; 07/02 / 2013＆＃34;，＆＃34; 07/03 / 2013＆＃34;，＆＃34; 07/04 / 2015＆＃34 ;，＆＃34; 07/06 / 2015＆＃34;，＆＃34; 07/07/2011＆＃34;，＆＃34; 08/06 / 2009＆＃34;，＆＃34; 08/06 / 2015＆＃34;，＆＃34; 08/07 / 2012＆＃34 ;，＆＃34; 08/08/2012＆＃34;，＆＃34; 09/07 / 2015＆＃34;，＆＃34; 09/08/2011＆＃34;，＆＃34; 10/07 / 2011＆＃34;，＆＃34; 10/07 / 2013＆＃34 ;，＆＃34; 10/07 / 2015＆＃34;，＆＃34; 10/08/2015＆＃34;，＆＃34; 11/07 / 2012＆＃34;，＆＃34; 11/08/2011＆＃34;，＆＃34; 11/08 / 2012＆＃34 ;，＆＃34; 12/03/2014＆＃34;，＆＃34; 12/03 / 2015＆＃34;，＆＃34; 12/06 / 2015＆＃34;，＆＃34; 13/06 / 2013＆＃34;，＆＃34; 13/07 / 2012＆＃34 ;，＆＃34; 14/07 / 2015＆＃34;，＆＃34; 14/08/2012＆＃34;，＆＃34; 15/08/2011＆＃34;，＆＃34; 16/02/2009＆＃34;，＆＃34; 17/07 / 2011＆＃34 ;，＆＃34; 17/07 / 2012＆＃34;，＆＃34; 17/08/2011＆＃34;，＆＃34; 18/02/2009＆＃34;，＆＃34; 18/07/2011＆＃34;，＆＃34; 18/08/2011＆＃34 ;，＆＃34; 19/07/2011＆＃34;，＆＃34; 19/08/2011＆＃34;，＆＃34; 19/08/2015＆＃34;，＆＃34; 20/06 / 2011＆＃34;，＆＃34; 20/06 / 2015＆＃34 ;，＆＃34; 20/07/2012＆＃34;，＆＃34; 21/02/2009＆＃34;，＆＃34; 21/06 / 2011＆＃34;，＆＃34; 21 / 08/2012＆＃34;，＆＃34; 22/06 / 2011＆＃34 ;，＆＃34; 23/08/2012＆＃34;，＆＃34; 24/07 / 2011＆＃34;，＆＃34; 24/08/2011＆＃34;，＆＃34; 26 / 06/2011＆＃34;，＆＃34; 26/07 / 2011＆＃34 ;，＆＃34; 26/08/2011＆＃34;，＆＃34; 26/08/2012＆＃34;，＆＃34; 27/07 / 2015＆＃34;，＆＃34; 28/03 / 2015＆＃34;，＆＃34; 28/07 / 2011＆＃34 ;，＆＃34; 28/08/2012＆＃34;，＆＃34; 29/03/2015＆＃34;，＆＃34; 29/07 / 2011＆＃34;，＆＃34; 29/08/2011＆＃34;，＆＃34; 30/04 / 2015＆＃34 ;，＆＃34; 30/07/2012＆＃34;，＆＃34; 30/08/2011＆＃34;，＆＃34; 30/08/2012＆＃34;，＆＃34; 31/01 / 2013＆＃34;，＆＃34; 31/08/2011＆＃34 ;），class =＆＃34; factor＆＃34;）， Final.ID =结构（c（22L，12L，12L，28L，12L，17L），。Label = c（＆＃34; SWT1＆＃34;，＆＃34; SWT11＆＃34;，＆＃34; SWT13＆＃34;，＆＃34; SWT14＆＃34;，＆＃34; SWT15＆＃34;，＆＃34; SWT16＆＃34;，＆＃34; SWT17＆＃34;，＆＃34; SWT19＆＃34;，＆＃34; SWT2＆＃34;，＆＃34; SWT21＆＃34;，＆＃34; SWT22＆＃34;，＆＃34; SWT23＆＃34;，＆＃34; SWT24＆＃34;，＆＃34; SWT27＆＃34;，＆＃34; SWT28＆＃34;，＆＃34; SWT29＆＃34;，＆＃34; SWT3＆＃34;，＆＃34; SWT30＆＃34;，＆＃34; SWT32＆＃34;，＆＃34; SWT37＆＃34;，＆＃34; SWT38＆＃34;，＆＃34; SWT45＆＃34;，＆＃34; SWT46＆＃34;，＆＃34; SWT47＆＃34;，＆＃34; SWT48＆＃34;，＆＃34; SWT49＆＃34;，＆＃34; SWT5＆＃34;，＆＃34; SWT50＆＃34;，＆＃34; SWT51＆＃34;，＆＃34; SWT52＆＃34;，＆＃34; SWT56＆＃34;，＆＃34; SWT58＆＃34;，＆＃34; SWT6＆＃34;，＆＃34; SWT61＆＃34;，＆＃34; SWT62＆＃34;，＆＃34; SWT65＆＃34;，＆＃34; SWT7＆＃34;，＆＃34; SWT73＆＃34;，＆＃34; SWT8＆＃34;，＆＃34; SWT9＆＃34;，＆＃34; T-014＆＃34;，＆＃34 ; T001＆＃34;，＆＃34; T002＆＃34;，＆＃34; T003＆＃34;，＆＃34; T004＆＃34;，＆＃34; T005＆＃34;，＆＃34; T005CC＆＃34;，＆＃34; T006＆＃34;，＆＃34; T006C＆＃34;，＆＃34; T009＆＃34;，＆＃34; T010＆＃34;，＆＃34; T010C＆＃34;，＆＃34; T010CC＆＃34;，＆＃34; T011＆＃34;，＆＃34; T012＆＃34;，＆＃34; T013＆＃34;，＆＃34; T014＆＃34;，＆＃34; T015＆＃34;，＆＃34; T015CC＆＃34;，＆＃34; T016＆＃34;，＆＃34; T018＆＃34;，＆＃34; T018C＆＃34;，＆＃34; T018CC＆＃34;，＆＃34; T018CCC＆＃34;，＆＃34; T019＆＃34;，＆＃34; T019C＆＃34;，＆＃34; T019CC＆＃34;，＆＃34; T020＆＃34;，＆＃34; T021＆＃34;，＆＃34; T021C＆＃34;，＆＃34; T021CC＆＃34;，＆＃34; T021CCC＆＃34;，＆＃34; T022＆＃34;，＆＃34; T022C＆＃34;，＆＃34; T022CC＆＃34;，＆＃34; T023＆＃34;，＆＃34; T024＆＃34;，＆＃34; T025＆＃34;，＆＃34; T027＆＃34;，＆＃34; T029＆＃34;，＆＃34; T034＆＃34;，＆＃34; T041＆＃34;，＆＃34; T041C＆＃34;，＆＃34; T042＆＃34;，＆＃34; T043＆＃34;，＆＃34; T044＆＃34;，＆＃34; T044C＆＃34;，＆＃34; T045＆＃34;，＆＃34; T045C＆＃34;，＆＃34; T046＆＃34;，＆＃34; T046C＆＃34;，＆＃34; T047＆＃34;，＆＃34; T047C＆＃34;，＆＃34; T048＆＃34;，＆＃34; T049＆＃34;，＆＃34; T050＆＃34;，＆＃34; T051＆＃34;，＆＃34; T052＆＃34;，＆＃34; T053＆＃34;，＆＃34; T053C＆＃34;，＆＃34; T054＆＃34;，＆＃34; T056＆＃34;，＆＃34; T056C＆＃34;，＆＃34; T057＆＃34;，＆＃34; T058＆＃34;，＆＃34; T059＆＃34;，＆＃34; T060＆＃34;，＆＃34; T060C＆＃34;，＆＃34; T061＆＃34;，＆＃34; T063＆＃34;，＆＃34; T065＆＃34;，＆＃34; T065C＆＃34;，＆＃34; T068＆＃34;，＆＃34; T070＆＃34;，＆＃34; T071＆＃34;，＆＃34; T072＆＃34;，＆＃34; T073＆＃34;，＆＃34; T074＆＃34;，＆＃34; T079＆＃34;，＆＃34; T082＆＃34;，＆＃34; T084＆＃34;，＆＃34; T086＆＃34;，＆＃34; T087＆＃34;，＆＃34; T087C＆＃34;，＆＃34; T089＆＃34;，＆＃34; T091＆＃34;，＆＃34; T091C＆＃34;，＆＃34; T094＆＃34;，＆＃34; T095＆＃34;，＆＃34; T096＆＃34;，＆＃34; T097＆＃34;，＆＃34; T097CC＆＃34;，＆＃34; T098＆＃34;，＆＃34; T099＆＃34;，＆＃34; T100＆＃34;，＆＃34; T101＆＃34;，＆＃34; T101C＆＃34;，＆＃34; T102＆＃34;，＆＃34; T102C＆＃34;，＆＃34; T103＆＃34;，＆＃34; T104＆＃34;，＆＃34; T113＆＃34;，＆＃34; T115＆＃34;，＆＃34; T117＆＃34;，＆＃34; T118＆＃34;，＆＃34; T118C＆＃34;，＆＃34; T123＆＃34;，＆＃34; T124＆＃34;，＆＃34; T124C＆＃34;，＆＃34; T125＆＃34;，＆＃34; T126＆＃34;，＆＃34; T127＆＃34;，＆＃34; T128＆＃34;，＆＃34; T129＆＃34;，＆＃34; T130＆＃34;，＆＃34; T131＆＃34;，＆＃34; T132＆＃34;，＆＃34; T133＆＃34;，＆＃34; T133C＆＃34;，＆＃34; T134＆＃34;，＆＃34; T135＆＃34;，＆＃34; T136＆＃34;，＆＃34; T137＆＃34;，＆＃34; T138＆＃34;，＆＃34; T139＆＃34;，＆＃34; U011＆＃34;），class =＆＃34; factor＆＃34;），Data = structure（c（1L， 1L，1L，1L，1L，1L），。标签= c（＆＃34; Acoustic＆＃34;，＆＃34; Photo＆＃34;），class =＆＃34; factor＆＃34;））。。Name = c（＆＃34;年＆＃34;，＆＃34;日期＆＃34;，＆＃34; Final.ID＆＃34;，＆＃34;数据＆＃34;），row.names = c（NA，6L），class =＆＃34; data.frame＆＃34）

Answer 1

Min不起作用，因为Date列是一个因素，首先需要将其转换为Date，然后轻按：

df$Date <- as.Date(as.character(df$Date), tryFormats =  "%d/%m/%Y")
dates<-as.Date(tapply(df$Date, df$Final.ID, min), origin="1970-01-01")
dates[!is.na(dates)]
#>        SWT23         SWT3        SWT45        SWT50 
#> "2009-03-02" "2011-07-07" "2009-02-18" "2011-06-26"

＆＃39;民＆＃39;对于遇到历史数据的因素没有意义，R Studio

1 个答案: