Japanese currency formatting for readability - php

Question

I'd like to format Japanese currency into the standard "quickly readable" format.
Basically, all amounts over 10,000 yen are written using the character "万" (pronounced "man").
More on "万"
http://www.romajidesu.com/kanji/%E4%B8%87
So, 1,000,000 yen would simply be 100万 or "one hundred man". That's roughly $1,000 USD.
Virtually no one in Japan would ever say "one million yen". The currency is always broken into 10,000 yen bundles.
Consequently, when you buy a car, the sticker on the windshield says (e.g.) "140万"
So, I'd like to display that format. However, number_format, I believe, does not allow for defining the separation at 10,000, and money_format is likewise unhelpful.
Any thoughts on a best practice method for accomplishing this?
In summary:
10,000 yen should read 1万
100,000 yen should read 10万
1,000,000 yen should read 100万

Answer 1

I have ever written that in my WordPress plugin,
/**
* convert number expressions to value
*
* #assert ("34000") == "3万4000円"
* #assert ("123456.789") == "12万3457円"
* #assert ("1234567890") == "12億3456万7890円"
* #assert ("92610000000000") == "92兆6100億円"
*/
public static function formatInJapanese($value) {
$isApproximate = false;
$formatted = '';
if ($value > 1000000000000) {
if ($value % 1000000000000 !== 0) {
$isApproximate = true;
}
$unitValue = floor($value / 1000000000000);
$formatted .= $unitValue . '兆';
$value -= $unitValue * 1000000000000;
}
if ($value > 100000000) {
if ($value % 100000000 !== 0
&& !$isApproximate) {
$isApproximate = true;
}
$unitValue = floor($value / 100000000);
$formatted .= $unitValue . '億';
$value -= $unitValue * 100000000;
}
if ($value > 10000) {
if ($value % 10000 !== 0
&& !$isApproximate) {
$isApproximate = true;
}
$unitValue = floor($value / 10000);
$formatted .= $unitValue . '万';
$value -= $unitValue * 10000;
}
if ($value != 0) {
$formatted .= round($value);
}
return $formatted . '円';
}
It only works with man, oku and cho.
Quick search gives me that Ruby gem number_to_yen doing similar.

Answer 2

The solution I came up with is similar to the above.
function format_yen_for_display($yenAmount)
{
/*
Converts Japanese currency to easily readable local format
10,000 yen should read 1万
100,000 yen should read 10万
1,000,000 yen should read 100万
1,259,000 yen should read 125万 9,000円
*/
if($yenAmount > 10000)
{
//amount over 1万
$manYen = floor($yenAmount/10000);
//amount under 1万
$remainderYen = ($yenAmount - ($manYen * 10000));
//concat
$returnNum = "<span class=\"ylarge\">" . $manYen . "万</span>";
//if remainder is more than zero, show it
if($remainderYen > 0)
{
//format remainder with thousands separator
$remainderYen = number_format($remainderYen);
$returnNum .= "<span class=\"ysmall\">" . $remainderYen ."円</span>";
}
}
else
{
$returnNum = "<span class=\"ylarge\">" . $yenAmount . "円</span>";
}
return $returnNum;
}