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package units
// SI units.
type SI int64
// SI unit multiples.
const (
Kilo SI = 1000
Mega = Kilo * 1000
Giga = Mega * 1000
Tera = Giga * 1000
Peta = Tera * 1000
Exa = Peta * 1000
)
func MakeUnitMap(suffix, shortSuffix string, scale int64) map[string]float64 {
res := map[string]float64{
shortSuffix: 1,
// see below for "k" / "K"
"M" + suffix: float64(scale * scale),
"G" + suffix: float64(scale * scale * scale),
"T" + suffix: float64(scale * scale * scale * scale),
"P" + suffix: float64(scale * scale * scale * scale * scale),
"E" + suffix: float64(scale * scale * scale * scale * scale * scale),
}
// Standard SI prefixes use lowercase "k" for kilo = 1000.
// For compatibility, and to be fool-proof, we accept both "k" and "K" in metric mode.
//
// However, official binary prefixes are always capitalized - "KiB" -
// and we specifically never parse "kB" as 1024B because:
//
// (1) people pedantic enough to use lowercase according to SI unlikely to abuse "k" to mean 1024 :-)
//
// (2) Use of capital K for 1024 was an informal tradition predating IEC prefixes:
// "The binary meaning of the kilobyte for 1024 bytes typically uses the symbol KB, with an
// uppercase letter K."
// -- https://en.wikipedia.org/wiki/Kilobyte#Base_2_(1024_bytes)
// "Capitalization of the letter K became the de facto standard for binary notation, although this
// could not be extended to higher powers, and use of the lowercase k did persist.[13][14][15]"
// -- https://en.wikipedia.org/wiki/Binary_prefix#History
// See also the extensive https://en.wikipedia.org/wiki/Timeline_of_binary_prefixes.
if scale == 1024 {
res["K"+suffix] = float64(scale)
} else {
res["k"+suffix] = float64(scale)
res["K"+suffix] = float64(scale)
}
return res
}
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