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rmatrixintegernumeric

Transform every column of a matrix from numerics to integers in R

I need to transform every columns of a R matrix object from numeric to integer.

A description of the matrix:

> dim(path_abundances)
202  48

It looks like this (but with 202 rows and 48 columns):

enter image description here

When looking for questions made here by other users, I found this solution to transform, from numeric to integer (the inverse of what I want), the columns 2 to 13 of a matrix named "dades":

dades[2:13] <- lapply(dades[2:13], as.numeric)

Applied to my specific situation, I tried with:

> path_abundances[1:202] <- lapply(path_abundances[1:202], as.integer)

when looking for the output, it was a list of 202 elements, in which each of them is the value for the i-th row of the first column but withouth the decimals (as expected for an integer):

  1. 512884
  2. 379358
  3. 319740
  4. etc

As said above, I want to transform every column to an integer in a matrix-class output.

Thanks for reading and for your answers in advance

-- EDIT to add an example:

matrix(data= c(path_abundances[1:3,2], path_abundances[1:3,3], path_abundances[1:3,4]), ncol = 3, byrow = F)

         [,1]     [,2]     [,3]
[1,] 512884.5 493049.7 577625.5
[2,] 379358.8 343425.7 394776.8
[3,] 319740.8 327932.6 417228.9

I want this matrix, which each column is numeric-class, to has every column as integer-class

Solution

  • You can use storage.mode:

    set.seed(101); m <- matrix(rnorm(9,mean=20,sd=3), 3,3)
storage.mode(m) <- "integer"
m
     [,1] [,2] [,3]
[1,]   19   20   21
[2,]   21   20   19
[3,]   17   23   22

    Note that this will truncate, rather than round, to integer - in case that matters to you.