R 将数据帧转换为矩阵

如何将数据帧“水果”转换为矩阵

> fruits
      Month Apple   Mango   Banana
1      June  149579 36051   28124
2      July  198742 37228   30354
3    August  397145 36483   31140
4 September  329559 37101   31588
5   October  144107 35917   29444
6  November   19432  8587    5382
7  December       0     0       0

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我想将月份和水果名称作为矩阵的头部

我们可以在不使用第一列的情况下对“水果”列进行子集，在第一列更改“水果”的行名称，并转换为矩阵（

as.matrix

）

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as.matrix（'row.names我想这是您想要的，但是最好按照@akrun的建议显示预期的输出：

# convert the number columns to a matrix
Mfruits <- as.matrix( fruits[ , 2:4 ] )
# get the months as column names
row.names( Mfruits ) <- fruits[ , 1 ]
> Mfruits
           Apple Mango Banana
June      149579 36051  28124
July      198742 37228  30354
August    397145 36483  31140
September 329559 37101  31588
October   144107 35917  29444
November   19432  8587   5382
December       0     0      0

# check whether you really have a matrix
str( Mfruits )
int [1:7, 1:3] 149579 198742 397145 329559 144107 19432 0 36051 37228 36483 ...
- attr(*, "dimnames")=List of 2
 ..$ : chr [1:7] "June" "July" "August" "September" ...
 ..$ : chr [1:3] "Apple" "Mango" "Banana"

#将数字列转换为矩阵
Mfruits您可以显示预期的输出。您是否需要
库（重塑）；acast（melt（fruits，id.var='Month'），variable~Month，value.var='value'）
或者它是
作为.matrix（'row.names'）您是救世主。谢谢。我正在寻找第二个答案。
# convert the number columns to a matrix
Mfruits <- as.matrix( fruits[ , 2:4 ] )
# get the months as column names
row.names( Mfruits ) <- fruits[ , 1 ]
> Mfruits
           Apple Mango Banana
June      149579 36051  28124
July      198742 37228  30354
August    397145 36483  31140
September 329559 37101  31588
October   144107 35917  29444
November   19432  8587   5382
December       0     0      0

# check whether you really have a matrix
str( Mfruits )
int [1:7, 1:3] 149579 198742 397145 329559 144107 19432 0 36051 37228 36483 ...
- attr(*, "dimnames")=List of 2
 ..$ : chr [1:7] "June" "July" "August" "September" ...
 ..$ : chr [1:3] "Apple" "Mango" "Banana"