wconv function

1-D or 2-D convolution

Compute the one- or two-dimensional convolution of two vectors or matrices.

wconv(
  type = c("1d", "2d", "row", "column"),
  a,
  b,
  shape = c("full", "same", "valid")
)

Arguments

• type: Numeric or character, specifies the type of convolution to perform:

  • "1d": For a and b as (coerced to) vectors, perform 1-D convolution of a and b;

  • "2d: For a and b as (coerced to) matrices, perform 2-D convolution of a and b;

  • "row": For a as (coerced to) a matrix, and b

     (coerced to) a vector, perform the 1-D convolution of the rows of `a`
     
     and `b`;
    

  • "column": For a as (coerced to) a matrix, and b

     (coerced to) a vector, perform the 1-D convolution of the colums of `a` and `b`;
    

• a, b: Input vectors or matrices, coerced to numeric.

• shape: Subsection of convolution, partially matched to:

  • "full": Return the full convolution (default)
  • "same": Return the central part of the convolution with the same size as A. The central part of the convolution begins at the indices floor(c(nrow(b), ncol(b)) / 2 + 1)
  • "valid": Return only the parts which do not include zero-padded edges. The size of the result is max(c(nrow(a), ncol(b)) - c(nrow(b), ncol(b)) + 1, 0)

Returns

Convolution of input matrices, returned as a matrix or a vector.

Examples

a <- matrix(1:16, 4, 4)
b <- matrix(1:9, 3,3)
w <- wconv('2', a, b)
w <- wconv('1', a, b, 'same')
w <- wconv('r', a, b)
w <- wconv('r', a, c(0,1), 'same')
w <- wconv('c', a, c(0,1), 'valid')

See Also

conv

Author(s)

Lukas Reichlin, lukas.reichlin@gmail.com .

Conversion to R by Geert van Boxtel, G.J.M.vanBoxtel@gmail.com .