将训练数据映射到元数据

Question

我想转换元数据映射火车数据。因为经度和纬度不适合我的火车数据。所以我将使用元数据距离的平均值。我尝试过合并功能，但效果不佳。

示例：

1) 训练数据

station  log  lat
      A  123  127
      B  121  126
      C  127  129
      D  113  118
      E  119  118

2) 元数据

from  to
   A   C
   B   C
   A   D
   A   E
   D   E

3) 期望输出

from fromlog fromlat tolog tolat
   A     123     127   127   129
   B     121     126   127   129
   A     123     127   113   118
   A     123     127   119   118
   D     113     118   119   118

Answer 1

这是一种选择

library(dplyr)
d1 <- inner_join(df1, df2,  by = c('station' =  'to')) %>%
    select(tolog = log, tolat = lat) 
d2 <- inner_join(df1, df2, by = c('station' = 'from')) %>%
    select(fromlog = log, fromlat = lat)
bind_cols(df2 %>% 
             select(from), d2, d1)

Answer 2

在 base R 中，我们可以在 lapply 调用中使用 match，

do.call(cbind.data.frame, unlist(lapply(df2, function(x) {
     inds <- match(x, df1$station)
     list(log = df1$log[inds], lat = df1$lat[inds])
}), recursive = FALSE))

#  from.log from.lat to.log to.lat
#1      123      127    127    129
#2      121      126    127    129
#3      123      127    113    118
#4      123      127    119    118
#5      113      118    119    118

数据

df1 <- structure(list(station = c("A", "B", "C", "D", "E"), log = c(123L, 
121L, 127L, 113L, 119L), lat = c(127L, 126L, 129L, 118L, 118L
)), row.names = c(NA, -5L), class = "data.frame")

df2 <- structure(list(from = c("A", "B", "A", "A", "D"), to = c("C", 
"C", "D", "E", "E")), row.names = c(NA, -5L), class = "data.frame")

将训练数据映射到元数据

mapping train data to meta data

mapping

r

geo