Apply a function to summarize rows/columns that assigned to the same level by a factor vector.
summarizeRows(matrix, factor, fun = mean, ...)A numeric matrix
A vector of factors, either of the length of
nrow(matrix) (for summarizeRows), or the length of
ncol(matrix) (for summarizeColumns).
A function or a name for a function, the summarizing function applied to rows/columns sharing the same level
Further parameters passed to the function
A matrix, the dimension will be determined by the number of levels of the factor vector.
NA levels are neglected, and corresponding rows/columns will not
contribute to the summarized matrix.
summarizeCols is synonymous to summarizeColumns
my.matrix <- matrix(1:25, nrow=5)
print(my.matrix)
#> [,1] [,2] [,3] [,4] [,5]
#> [1,] 1 6 11 16 21
#> [2,] 2 7 12 17 22
#> [3,] 3 8 13 18 23
#> [4,] 4 9 14 19 24
#> [5,] 5 10 15 20 25
my.factor <- factor(c("A", "B", "A", "C", "B"))
summarizeRows(matrix=my.matrix, factor=my.factor, fun=mean)
#> [,1] [,2] [,3] [,4] [,5]
#> A 2.0 7.0 12.0 17.0 22.0
#> B 3.5 8.5 13.5 18.5 23.5
#> C 4.0 9.0 14.0 19.0 24.0
summarizeRows(matrix=my.matrix, factor=my.factor, fun=prod)
#> [,1] [,2] [,3] [,4] [,5]
#> A 3 48 143 288 483
#> B 10 70 180 340 550
#> C 4 9 14 19 24
summarizeColumns(matrix=my.matrix, factor=my.factor, fun=mean)
#> A B C
#> [1,] 6 13.5 16
#> [2,] 7 14.5 17
#> [3,] 8 15.5 18
#> [4,] 9 16.5 19
#> [5,] 10 17.5 20
summarizeColumns(matrix=my.matrix, factor=my.factor, fun=prod)
#> A B C
#> [1,] 11 126 16
#> [2,] 24 154 17
#> [3,] 39 184 18
#> [4,] 56 216 19
#> [5,] 75 250 20
## NA values in factor
my.na.factor <- factor(c("A", "B", "A", "C", NA))
summarizeRows(matrix=my.matrix, factor=my.na.factor, fun=mean)
#> [,1] [,2] [,3] [,4] [,5]
#> A 2 7 12 17 22
#> B 2 7 12 17 22
#> C 4 9 14 19 24
summarizeRows(matrix=my.matrix, factor=my.na.factor, fun=prod)
#> [,1] [,2] [,3] [,4] [,5]
#> A 3 48 143 288 483
#> B 2 7 12 17 22
#> C 4 9 14 19 24
summarizeColumns(matrix=my.matrix, factor=my.na.factor, fun=mean)
#> A B C
#> [1,] 6 6 16
#> [2,] 7 7 17
#> [3,] 8 8 18
#> [4,] 9 9 19
#> [5,] 10 10 20
summarizeColumns(matrix=my.matrix, factor=my.na.factor, fun=prod)
#> A B C
#> [1,] 11 6 16
#> [2,] 24 7 17
#> [3,] 39 8 18
#> [4,] 56 9 19
#> [5,] 75 10 20