DecimalUtils (jOpenDocument API 1.3)

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org.jopendocument.util
Class DecimalUtils

java.lang.Object
 extended by org.jopendocument.util.DecimalUtils

public class DecimalUtils
extends Object
extends Object

Field Summary
`static MathContext`	`HIGH_PRECISION` Useful to pass to `BigDecimal.divide(BigDecimal, MathContext)` since : 1234,567.divide(33000) throws java.lang.ArithmeticException: Non-terminating decimal expansion; no exact representable decimal result 1234,567.divide(33000, RoundingMode.HALF_UP) = 0,037 : since it isn't exact uses the dividend scale, thus loosing a lot of precision 1234,567.divide(33000, HIGH_PRECISION) = 0.03741112121212121212121212121212121 You also can't just use the precision of the dividend : lowPrecision = new BigDecimal("1E+3"); lowPrecision.divide(new BigDecimal("7E+5"), new MathContext(lowPrecision.precision()))) == 0.001; lowPrecision.divide(new BigDecimal("7E+5"), HIGH_PRECISION) == 0.001428571428571428571428571428571429; Note: `MathContext.DECIMAL128` is different since it uses `RoundingMode.HALF_EVEN`

Field Summary

static MathContext HIGH_PRECISION
Useful to pass to BigDecimal.divide(BigDecimal, MathContext) since : 1234,567.divide(33000) throws java.lang.ArithmeticException: Non-terminating decimal expansion; no exact representable decimal result 1234,567.divide(33000, RoundingMode.HALF_UP) = 0,037 : since it isn't exact uses the dividend scale, thus loosing a lot of precision 1234,567.divide(33000, HIGH_PRECISION) = 0.03741112121212121212121212121212121 You also can't just use the precision of the dividend : lowPrecision = new BigDecimal("1E+3"); lowPrecision.divide(new BigDecimal("7E+5"), new MathContext(lowPrecision.precision()))) == 0.001; lowPrecision.divide(new BigDecimal("7E+5"), HIGH_PRECISION) == 0.001428571428571428571428571428571429; Note: MathContext.DECIMAL128 is different since it uses RoundingMode.HALF_EVEN

Constructor Summary
`DecimalUtils()`

Method Summary
`static int`	`decimalDigits(BigDecimal d)` The number of decimal digits.
`static int`	`intDigits(BigDecimal d)` The number of int digits.
`static BigDecimal`	`round(BigDecimal d, int decimalDigits)`
`static BigDecimal`	`round(BigDecimal d, int decimalDigits, RoundingMode rmode)` Round the passed BigDecimal so that only `decimalDigits` remain after the point.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

HIGH_PRECISION

public static final MathContext HIGH_PRECISION

Useful to pass to BigDecimal.divide(BigDecimal, MathContext) since :

1234,567.divide(33000) throws java.lang.ArithmeticException: Non-terminating decimal expansion; no exact representable decimal result
1234,567.divide(33000, RoundingMode.HALF_UP) = 0,037 : since it isn't exact uses the dividend scale, thus loosing a lot of precision
1234,567.divide(33000, HIGH_PRECISION) = 0.03741112121212121212121212121212121

You also can't just use the precision of the dividend :

 lowPrecision = new BigDecimal("1E+3");
 lowPrecision.divide(new BigDecimal("7E+5"), new MathContext(lowPrecision.precision()))) == 0.001;
 lowPrecision.divide(new BigDecimal("7E+5"), HIGH_PRECISION) == 0.001428571428571428571428571428571429;

Note: MathContext.DECIMAL128 is different since it uses RoundingMode.HALF_EVEN

Constructor Detail

DecimalUtils

public DecimalUtils()

Method Detail

intDigits

public static int intDigits(BigDecimal d)

The number of int digits.

Parameters:: d - the decimal to use, eg "123.45".
Returns:: number of int digits, never less than 1, eg 3.

decimalDigits

public static int decimalDigits(BigDecimal d)

The number of decimal digits.

Parameters:: d - the decimal to use, eg "123.45" or "120".
Returns:: number of decimal digits, never less than 0, eg 2 or 0.

round

public static BigDecimal round(BigDecimal d,
 int decimalDigits)

round

public static BigDecimal round(BigDecimal d,
 int decimalDigits,
 RoundingMode rmode)

Round the passed BigDecimal so that only decimalDigits remain after the point.

Parameters:: d - the decimal to use, eg "123.4567".; decimalDigits - the number of digits after the point, eg 1.; rmode - how to round.
Returns:: d rounded so that only decimalDigits remain, eg "123.5".