如何在循环中对数据进行子集然后对r中生成的数据帧数据进行循环

问题描述

您介意帮助我运行从子集中循环生成的数据帧。我想对每个子集数据进行以下操作来进行Mann-Kendall测试（库（rkt））：

  date     Year Month  Day sum-rainfall frac  overall-slope  Sens Slope           Seq
1   1911-10-01  1911    10  1   216.3   1911.11 278.5459    a)1911-2019: -0.85 mm/yr   1
2   1912-10-01  1912    10  1   275.3   1912.11 277.7006    a)1911-2019: -0.85 mm/yr    1
3   1913-10-01  1913    10  1   266.2   1913.11 276.8553    a)1911-2019: -0.85 mm/yr    1
.
. 
78  1988-10-01  1988    10  1   225.6   1988.11 213.4582    a)1911-2019: -0.85 mm/yr    4
79  1989-10-01  1989    10  1   234.6   1989.11 212.6129    a)1911-2019: -0.85 mm/yr    4
.   
.
108  2018-10-01 2018    10  1   206.8   2018.11 188.0994    a)1911-2019: -0.85 mm/yr    6
109 2019-10-01  2019    10  1   168.8   2019.11 187.2541    a)1911-2019: -0.85 mm/yr    6

for (i in rainfall_wet$Seq){  
  m<- assign(paste("segment_wet",i,sep = "_"),subset(rainfall_wet,Seq==i))
  FD<-rkt(m$Year,m$sum_rainfall,m$Month,TRUE)
  print(FD)
  FD$B
  b0<- median(m$sum_rainfall)-(FD$B* median(m$Year))
  m$overall_slope<- b0+(FD$B*m$Year)
  length(m$Year)
  a3<-as.character(m$Year[1]) 
  b3<-as.character(m$Year[length(m$Year)]) 
  z3<-as.character(lapply(FD$B,round,2))
  m$`Sens Slpe`<- paste("b)",a3,"-",b3,":"," ",z3,"mm/yr",sep='')
}

首先循环，我想对数据进行子集处理，然后再对每个

行进行其他处理

解决方法

像这样吗？

plyr::ddply(rainfall_wet,plyr::.(Seq),function(m){
  FD<-rkt(m$Year,m$sum_rainfall,m$Month,TRUE)
  print(FD)
  FD$B
  b0<- median(m$sum_rainfall)-(FD$B* median(m$Year))
  m$overall_slope<- b0+(FD$B*m$Year)
  length(m$Year)
  a3<-as.character(m$Year[1]) 
  b3<-as.character(m$Year[length(m$Year)]) 
  z3<-as.character(lapply(FD$B,round,2))
  m$`Sens Slpe`<- paste("b)",a3,"-",b3,":"," ",z3,"mm/yr",sep='')
  return(m)
}
)