remove_constant: Remove constant columns

In dmolitor/sparseprepr: Pre Processing for Sparse Matrices

Description

remove_constant() removes zero-variance columns from sparse and dense matrices.

Usage

remove_constant(x)

## S3 method for class 'CsparseMatrix'
remove_constant(x)

## S3 method for class 'matrix'
remove_constant(x)

Arguments

x	A matrix or CsparseMatrix.

Details

remove_constant() is an S3 generic with methods for:

• CsparseMatrix

• matrix

Value

x with zero-variance columns removed.

Examples

# Create a sparse matrix with constant columns
x <- Matrix::rsparsematrix(10, 3, 0.1)
colnames(x) <- paste0("x", 1:3)
x <- cbind(x, "x4" = 1, "x5" = 54)
# Print x
x

# Same matrix in dense format
xdense <- as.matrix(x)

# Drop constant columns
remove_constant(x)
remove_constant(xdense)

dmolitor/sparseprepr documentation built on Jan. 7, 2022, 9:58 p.m.