Package ch.obermuhlner.math.big

Class BigFloat

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<BigFloat>
    Direct Known Subclasses:
    BigFloat.SpecialBigFloat
    public class BigFloat
extends java.lang.Object
implements java.lang.Comparable<BigFloat>, java.io.Serializable
    A wrapper around BigDecimal which simplifies the consistent usage of the MathContext and provides a simpler API for calculations.

    Overview

    Every BigFloat instance has a reference to a BigFloat.Context that specifies the MathContext to be used for all calculations and values.

    The API for calculations is simplified and more consistent with the typical mathematical usage.

    • Factory methods for values:
      • valueOf(BigFloat)
      • valueOf(BigDecimal)
      • valueOf(int)
      • valueOf(long)
      • valueOf(double)
      • valueOf(String)
      • pi()
      • e()
    • All standard operators:
      • add(x)
      • subtract(x)
      • multiply(x)
      • remainder(x)
      • pow(y)
      • root(y)
    • Calculation methods are overloaded for different value types:
      • add(BigFloat)
      • add(BigDecimal)
      • add(int)
      • add(long)
      • add(double)
      • ...
    • Mathematical functions are written as they are traditionally are written:
      • abs(x)
      • log(x)
      • sin(x)
      • min(x1, x2, ...)
      • max(x1, x2, ...)
      • ...
    • Support for advanced mathematical functions:
      • sqrt(x)
      • log(x)
      • exp(x)
      • sin(x)
      • cos(x)
      • tan(x)
      • ...
    • Methods to access parts of a value:
      • getMantissa()
      • getExponent()
      • getIntegralPart()
      • getFractionalPart()
    • Equals and Hashcode methods:
      • equals(Object) that returns whether two BigFloat values are mathematically the same
      • hashCode() consistent with equals(Object)
    • Comparison methods:
      • isEqual(BigFloat)
      • isLessThan(BigFloat)
      • isLessThanOrEqual(BigFloat)
      • isGreaterThan(BigFloat)
      • isGreaterThanOrEqual(BigFloat)

    Usage

    Before doing any calculations you need to create a Context specifying the precision used for all calculations.

     Context context = BigFloat.context(100); // precision of 100 digits
 Context anotherContext = BigFloat.context(new MathContext(10, RoundingMode.HALF_UP); // precision of 10 digits, rounding half up

    The Context can then be used to create the first value of the calculation:

     BigFloat value1 = context.valueOf(640320);

    The BigFloat instance holds a reference to the Context. This context is then passed from calculation to calculation.

     BigFloat value2 = context.valueOf(640320).pow(3).divide(24);
 BigFloat value3 = BigFloat.sin(value2);

    The BigFloat result can be converted to other numerical types:

     BigDecimal bigDecimalValue = value3.toBigDecimal();
 double doubleValue = value3.toDouble();
 long longValue = value3.toLong();
 int intValue = value3.toInt();
    See Also:
    Serialized Form