在 R 中按类别划分矩阵值

Divide matrix values by category means in R

我有一个矩阵 (A) 包含 211 行和 6 列(每个时间段一个)和一个不同的矩阵 (B)包含211行2列,其中第二列包含分类信息(1-9)。

我的目标是创建一个新矩阵 (C),其中矩阵 A 中的每个值都是 value(A) 除以 (value (A) 按类别 (B))。我设法使用聚合函数计算每列每个类别的均值。这些存储在单独的数据框中,column_means,每个时间波都在单独的列中。这也包含有关 column_means[1].

中的组的信息

我不知道如何从这里开始,我正在寻找一个优雅的解决方案,以便我可以将这些知识转移到未来的项目中(并可能改进我现有的代码)。我的猜测是解决方案隐藏在 dplyr 的某个地方,一旦你知道它就相当简单。

感谢您的任何建议。

数据示例:

##each column here represents a wave:
initialmatrix <- structure(c(0.882647671948723, 0.847932241438909, 0.753052308699317, 
0.754977233408875, NA, 0.886095543329695, 0.849625252682829, 
0.78893884364632, 0.77111113840682, NA, 0.887255207679895, 0.851503493865384, 
0.812107856411831, 0.793982699495818, NA, 0.885212452552841, 
0.854894065774315, 0.815265718290737, 0.806766276556325, NA, 
0.882027335190646, 0.85386634818439, 0.818052477777012, 0.815997781565393, 
NA, 0.88245957310107, 0.855819521951304, 0.830425687228663, 0.820857689847061, 
NA), .Dim = 5:6, .Dimnames = list(NULL, c("V1", "V2", "V3", "V4", 
"V5", "V6")))

##the first column is unique ID, the 2nd the category:
categories <- structure(c(1L, 2L, 3L, 4L, 5L, 2L, 1L, 2L, 2L, 4L), .Dim = c(5L, 
2L), .Dimnames = list(NULL, c("V1", "V2")))

##the first column represents the category, column 1-6 the mean per category for each corresponding wave in "initialmatrix"
column.means <- structure(list(Group.1 = 1:5, x = c(0.805689153058216, 0.815006230419524, 
0.832326976776262, 0.794835253329865, 0.773041961434791), asset_means_2...2. = c(0.80050960343197, 
0.81923553710203, 0.833814773618545, 0.797834687980729, 0.780028077018158
), asset_means_3...2. = c(0.805053341257357, 0.828691564900149, 
0.833953165695685, 0.799381078569563, 0.785813047374534), asset_means_4...2. = c(0.806116664276125, 
0.832439754757116, 0.835982197159582, 0.801702200401293, 0.788814840753852
), asset_means_5...2. = c(0.807668548993891, 0.83801834926905, 
0.836036508152776, 0.803433961863399, 0.79014026195926), asset_means_6...2. = c(0.808800359101212, 
0.840923947682599, 0.839660313992458, 0.804901773257962, 0.793165113115977
)), row.names = c(NA, 5L), class = "data.frame")

这看起来像是 Superma 的工作......不等等......map2

library(dplyr)
library(purrr)

as_tibble(initialmatrix) %>%
  mutate(category = as.double(as_tibble(categories)$V2),
         across(starts_with('V'), 
                ~ unlist(map2(., category, ~ .x/mean(c(.x, .y)))))) %>%
  select(-category)

#       V1     V2     V3     V4     V5     V6
#    <dbl>  <dbl>  <dbl>  <dbl>  <dbl>  <dbl>
# 1  0.612  0.614  0.615  0.614  0.612  0.612
# 2  0.918  0.919  0.920  0.922  0.921  0.922
# 3  0.547  0.566  0.578  0.579  0.581  0.587
# 4  0.548  0.557  0.568  0.575  0.580  0.582
# 5  NA     NA     NA     NA     NA     NA    

这是你想要做的吗?

options(digits=3)
divisor <- column.means[categories[, 2], -1]
divisor
#         x asset_means_2...2. asset_means_3...2. asset_means_4...2. asset_means_5...2. asset_means_6...2.
# 2   0.815              0.819              0.829              0.832              0.838              0.841
# 1   0.806              0.801              0.805              0.806              0.808              0.809
# 2.1 0.815              0.819              0.829              0.832              0.838              0.841
# 2.2 0.815              0.819              0.829              0.832              0.838              0.841
# 4   0.795              0.798              0.799              0.802              0.803              0.805
initialmatrix/divisor
#         x asset_means_2...2. asset_means_3...2. asset_means_4...2. asset_means_5...2. asset_means_6...2.
# 2   1.083              1.082              1.071              1.063              1.053              1.049
# 1   1.052              1.061              1.058              1.061              1.057              1.058
# 2.1 0.924              0.963              0.980              0.979              0.976              0.988
# 2.2 0.926              0.941              0.958              0.969              0.974              0.976
# 4      NA                 NA                 NA                 NA                 NA                 NA