unpack_double.R

unpack_double <- function(x) {
  binary <- numToBits(x)    # little-endian binary representation
  structure(
    list(
      sign = binary[64],        # 1-bit sign
      exponent = binary[63:53], # 11-bit exponent
      mantissa = binary[52:1]   # 52-bit mantissa
    ),
    class = "unpacked_double"
  )
}

print.unpacked_double <- function(x, ...) {
  sign <- as.character(as.integer(x$sign))
  exponent <- paste(as.character(as.integer(x$exponent)), collapse = "")
  mantissa <- paste(as.character(as.integer(x$mantissa)), collapse = "")
  cat(sign, exponent, mantissa, "\n")
}

repack_double <- function(x) {
  s <- ifelse(as.integer(x$sign) == 0, 1, -1)
  p <- sum(as.integer(x$exponent) * 2^(10:0)) - 2^10 + 1
  v <- sum(as.integer(x$mantissa) * (2^(-1:(-52)))) + 1
  s * v * 2 ^ p
}