R/getsolvedmatrix.R

In weililab/scMAGeCK: Identify genes associated with multiple expression phenotypes in single-cell CRISPR screening data

# function definitions ##### version: 02-22-2019 should sync from the version in macbook:
# /Users/weili/Dropbox/work/cropseq/Shendure/nmeth18/multiple_guides_function.R

# perform matrix decomposition get A for Y=XA A= (X^TX)^-1X^TY Y: (cells * expressed genes) X:
# design matrix, (cells * KO genes), can also be (cells * double KO genes) A: (KO genes * expressed
# genes)
getsolvedmatrix <- function(Xm, Ym, lambda = 0.01) {
    # Amat=solve(Xmat,Ymat) # solve AX=B, or Xmat * A =Ymat
    TMmat_g = (t(Xm) %*% Xm) + lambda * diag(ncol(Xm))
    
    Amat_g = solve(TMmat_g) %*% t(Xm) %*% Ym
    return(Amat_g)
}
TRUE