Zero out matrix elements by a threshold test

Sets A[i,j] to 0 wherever the chosen comparison against x holds, leaving every other element unchanged – TDA's mnc (documented in tda.hlp). test chooses the comparison: "<=", "<", ">=", ">" (against the raw value), or the same four prefixed "abs" (against abs(A[i,j])).

Usage

tda_mnc(
  A,
  x,
  test = c("<=", "<", ">=", ">", "abs<=", "abs<", "abs>=", "abs>"),
  dir = tempfile("tda")
)

Arguments

A

a numeric matrix.

x

the threshold.

test

which comparison zeroes an element; see above.

dir

working directory.

Value

A numeric matrix.

See also

Other matrix algebra: tda_mcel(), tda_mcent(), tda_mch(), tda_mcross(), tda_mdiag(), tda_mev(), tda_mevs(), tda_midf(), tda_midf1(), tda_midf2(), tda_midf3(), tda_minvs(), tda_mkmet(), tda_mkp(), tda_mmul(), tda_mnrow(), tda_mpbl(), tda_mpfit(), tda_mpinv(), tda_mpit(), tda_mple(), tda_mpz(), tda_mscal1(), tda_msqrtd(), tda_msvd(), tda_mwvec()

Examples

A <- matrix(c(1, 5, 3, -2, 4, 6), 2, 3)
tda_mnc(A, 3, "<=")   # zero out every element <= 3
#>      [,1] [,2] [,3]
#> [1,]    0    0    4
#> [2,]    5    0    6