DecimalFormat

format decimal numbers with a specific pattern

Install

``
$ npm install decimal-format --save
`
or use pnpm
`
$ pnpm add decimal-format --save
`

Usage


`javascript
import DecimalFormat from 'decimal-format';

const df = new DecimalFormat('#,##0.0#');
df.format(1234.995); // 1,235.0
df.format(1234.956); // 1,234.96

const df1 = new DecimalFormat('#,##0.0#%');
df1.format(0.34995); // 35.0%

const df2 = new DecimalFormat('#,##0.0#‰');
df2.format(0.034993); // 34.99‰

const df3 = new DecimalFormat('￥#,##0.00元');
df3.format(1234.995); // ￥1,235.00元

const df4 = new DecimalFormat('0.00E');
df4.format(1234); // 1.23E3

const df5 = new DecimalFormat('0.00E+');
df5.format(1234); // 1.23E+3
`

RoundingMode defines the rounding modes of the formatting
`javascript
import DecimalFormat, { RoundingMode } from 'decimal-format';

const df = new DecimalFormat('#,##0.0#');
df.setRoundingMode(RoundingMode.UP); // round away from zero
df.format(2.1) // 3.0
df.format(-2.1) // -3.0

df.setRoundingMode(RoundingMode.UNNECESSARY) // assert that no rounding is necessary
df.format(2.11) // 2.11
df.format(2.123) // throw exception
``

RoundingMode

| Enum | Description |
| ----------- | ------------------------------------------------------------ |
| UP | round away from zero |
| DOWN | round towards zero |
| CEILING | round towards positive infinity |
| FLOOR | round towards negative infinity |
| HALF_UP | round towards "nearest neighbor" unless both neighbors are equidistant, in which case round up |
| HALF_DOWN | round towards "nearest neighbor" unless both neighbors are equidistant, in which case round down |
| HALF_EVEN | round towards the "nearest neighbor" unless both neighbors are equidistant, in which case round toward the even neighbor |
| UNNECESSARY | assert that the requested operation has an exact result, hence no rounding is necessary |