When “normalising” Decimal numbers it’s easy fall into something like this:
Decimal.normalize(Decimal.new("10.00"))
Decimal.new("1E+1")
which is technically correct but rather unusable when all I want from this “normalisation” is getting rid of unneeded trailing zeroes (in this case the insignificant decimal part) while keeping the numbers “human readable”. Decimal.round() is not an option because sometimes the decimal part can be significant. I can imagine of course some ways of doing this “manually” but since I guess I am not the first one to have such not-so-exotic need, maybe there’s a ready solution out there?
What do you need the normalized human-readable form for? Eyeballing values as you code along seems to be the only valid scenario I can think of.
You can serialize the decimal back into a string, too.
I present those to the user(s). if the number has no significant decimal digits, I’d like not to show them. IOW - I want the user to see “10” if the Decimal is “10.00” but I want her to see “10.5” if the Decimal is “10.50” and so on.
I know - that’s what I do. And…
iex(1)> Decimal.to_string(Decimal.new("10.00"))
"10.00"
iex(2)> Decimal.to_string(Decimal.normalize(Decimal.new("10.00")))
"1E+1"
You can do Decimal.to_string(decimal, :normal) to not get scientific formatting.
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Gosh… :red face and facepalm: RTFM. Sorry. Of course that does the trick. I couldn’t believe there was nothing ready out there.
