Decimal

The Decimal object is a core member of Quantify.

It simplifies operations with arbitrary precision reals (BigDecimal). It provides a very concise API through the use of static factories named $. This significantly reduces the amount of code necessary.

example:

@Test
public void testShowASimpleChainingVersusBigDecimal(){
BigDecimal result = new BigDecimal(125.75).subtract(new BigDecimal(100)).add(new BigDecimal(4.25)).divide(new BigDecimal(3), new MathContext(2));
assertEquals(TEN, result);
//versus
assertDecimal(10, $(125.75).minus(100).plus(4.25).divide(3));
}

What would you rather?

Let’s see how it simplifies Divisions, which, if not familiar with, can be quite tricky. Both of them produce 45:

@Test
public void testDivisionRoundedToInt(){
BigDecimal expected = new BigDecimal(312d).divide(new BigDecimal(7d), RoundingMode.HALF_EVEN);
assertEquals(new BigDecimal(45), expected);
assertDecimal(45, new Divide(312, 7).halfEven().eval());
}

or this simpler example:

@Test
public void testCompareDivisionWithDefaultPrecision(){
BigDecimal expected = new BigDecimal(312d).divide(new BigDecimal(7d), 10, RoundingMode.HALF_EVEN);
assertEquals(new BigDecimal(44.5714285714, new MathContext(12)), expected);
assertDecimal(44.5714285714, $(312).divide(7));
}