2016-09-23 99 views
1

我有基于行的迁移数据。将基于行的迁移数据转换为迁移矩阵

param <- c("A", "B", "C") 
df <- data.frame(Case1 = c("A", "A", "B", "B"), 
      Case2 = c("A", "C", "A", "B"), 
      Val = c(0.5,0.4,0.3,0.7)) 

所以这个数据帧貌似 Case1 Case2 Val 1 A A 0.5 2 A C 0.4 3 B A 0.3 4 B B 0.7 该行根据数据帧应该以一种“迁移矩阵”来transformend。

dd <- data.frame(cA = c(0.5, 0.3, 0), 
      cB = c(0, 0.7, 0), 
      cC = c(0.4,0,0)) 
rownames(dd) <- paste0("Case1","_", param) 
colnames(dd) <- paste0("Case2","_", param) 

因此迁移矩阵看起来像

Case2_A Case2_B Case2_C Case1_A 0.5 0.0 0.4 Case1_B 0.3 0.7 0.0 Case1_C 0.0 0.0 0.0

有谁知道一个很好的方法R中做到这一点?非常感谢你!

回答

0

随着基础R:

df 

    Case1 Case2 Val 
1  A  A 0.5 
2  A  C 0.4 
3  B  A 0.3 
4  B  B 0.7 

library(reshape2) 
levels(df$Case1) <- c(levels(df$Case1), 'C') 
df <- dcast(df, Case1~Case2, value.var='Val', drop=FALSE) 
rownames(df) <- paste('Case1', df[,1], sep='_') 
df <- df[-1] 
names(df) <- paste('Case2', names(df), sep='_') 
df[is.na(df)] <- 0.0 
df 

    Case2_A Case2_B Case2_C 
Case1_A  0.5  0.0  0.4 
Case1_B  0.3  0.7  0.0 
Case1_C  0.0  0.0  0.0 
1

您可以使用dplyrtidyr

library(dplyr); library(tidyr) 

df %>% 
     complete(Case1 = LETTERS[1:3], Case2 = LETTERS[1:3]) %>% 
     mutate_at(vars(starts_with("Case")), funs(paste("Case", ., sep = "_"))) %>% 
     spread(Case2, Val, fill = 0.0) 

# Source: local data frame [3 x 4] 

# Case1 Case_A Case_B Case_C 
# <chr> <dbl> <dbl> <dbl> 
#1 Case_A 0.5 0.0 0.4 
#2 Case_B 0.3 0.7 0.0 
#3 Case_C 0.0 0.0 0.0 

或者,如果你想保留的列数具体为:

df %>% 
     complete(Case1 = LETTERS[1:3], Case2 = LETTERS[1:3]) %>% 
     mutate(Case1 = paste('Case1', Case1, sep = "_"), 
      Case2 = paste('Case2', Case2, sep = "_")) %>% 
     spread(Case2, Val, fill = 0.0) 

# Source: local data frame [3 x 4] 

#  Case1 Case2_A Case2_B Case2_C 
#  <chr> <dbl> <dbl> <dbl> 
# 1 Case1_A  0.5  0.0  0.4 
# 2 Case1_B  0.3  0.7  0.0 
# 3 Case1_C  0.0  0.0  0.0 
0

一个base R选项在转换th之后将使用xtabs前两个柱为factorlevels指定为unlist ed列的unique水平,因此某些组合不会丢失。

Un1 <- sort(unique(unlist(df[1:2]))) 
df[1:2] <- lapply(df[1:2], factor, levels = Un1) 
res <- xtabs(Val~Case1+Case2, df) 

如果我们需要的dimnames

dimnames(res) <- Map(paste, names(dimnames(res)), dimnames(res), MoreArgs = list(sep="_")) 
names(dimnames(res)) <- NULL 
res 
#   Case2_A Case2_B Case2_C 
#Case1_A  0.5  0.0  0.4 
#Case1_B  0.3  0.7  0.0 
#Case1_C  0.0  0.0  0.0