Format Number

format_number.R

# # MIT License
#
# Copyright (c) 2024 Mickaël Canouil
#
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format_number <- function(x, prefix = NULL) {
  x_sign <- signif(x, digits = 3)
  x_fmt <- character(length = length(x))
  
  x_fmt[x == 0] <- 0
  x_fmt[abs(x) > 1e-2 & x != 0] <- prettyNum(
    x = x_sign[abs(x) > 1e-2 & x != 0], 
    scientific = FALSE, 
    justify = "none",
    digits = 3, 
    nsmall = 3, 
    trim = TRUE,
    width = 3
  )
  x_fmt[abs(x) <= 1e-2 & x != 0] <- gsub(
    "^(.*)e[+]*([-]*)0*(.*)$", 
    "\\1 %*% 10^\\2\\3", 
    prettyNum(
      x = x_sign[abs(x) <= 1e-2 & x != 0], 
      scientific = TRUE, 
      justify = "none",
      digits = 3, 
      nsmall = 3, 
      trim = TRUE,
      width = 3
    )
  )

  if (is.null(prefix)) {
    gsub("^1 \\%\\*\\% ", "", x_fmt)
  } else {
    paste(prefix, "==", gsub("^1 \\%\\*\\% ", "", x_fmt))
  }
}