Package org.apfloat

Class Apfloat

java.lang.Object

java.lang.Number

org.apfloat.Apcomplex

org.apfloat.Apfloat

All Implemented Interfaces:

Serializable, Comparable<Apfloat>, Formattable

Direct Known Subclasses:

Aprational

public class Apfloat
extends Apcomplex
implements Comparable<Apfloat>

Arbitrary precision floating-point number class.

Apfloat numbers are immutable.

A pitfall exists with the constructors Apfloat(float,long) and Apfloat(double,long). Since floats and doubles are always represented internally in radix 2, the conversion to any other radix usually causes round-off errors, and the resulting apfloat won't be accurate to the desired number of digits.

For example, 0.3 can't be presented exactly in base 2. When you construct an apfloat like new Apfloat(0.3f, 1000), the resulting number won't be accurate to 1000 digits, but only to roughly 7 digits (in radix 10). In fact, the resulting number will be something like 0.30000001192092896...

If you want an exact representation of a floating-point primitive (which is a rational number), you can use Aprational(double).

Version:

1.11.1

Author:

Mikko Tommila

See Also:

• ApfloatMath
• Serialized Form

Field Summary

Fields inherited from class org.apfloat.Apcomplex

DEFAULT, I, INFINITE, ONE, REAL_ABS_IMAG_ORDER, REAL_IMAG_ORDER, ZERO

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Apfloat()	Default constructor.
	Apfloat(double value)	Constructs an apfloat from the specified double.
	Apfloat(double value, long precision)	Constructs an apfloat from the specified double and precision.
	Apfloat(double value, long precision, int radix)	Constructs an apfloat from the specified double, precision and radix.
	Apfloat(float value)	Constructs an apfloat from the specified float.
	Apfloat(float value, long precision)	Constructs an apfloat from the specified float and precision.
	Apfloat(float value, long precision, int radix)	Constructs an apfloat from the specified float, precision and radix.
	Apfloat(long value)	Constructs an apfloat from the specified long.
	Apfloat(long value, long precision)	Constructs an apfloat from the specified long and precision.
	Apfloat(long value, long precision, int radix)	Constructs an apfloat from the specified long, precision and radix.
	Apfloat(PushbackReader in)	Reads an apfloat from a stream using default precision and radix.
	Apfloat(PushbackReader in, long precision)	Reads an apfloat from a stream using the specified precision.
	Apfloat(PushbackReader in, long precision, int radix)	Reads an apfloat from a stream using the specified precision and radix.
	Apfloat(String value)	Constructs an apfloat from the specified string.
	Apfloat(String value, long precision)	Constructs an apfloat from the specified string and precision.
	Apfloat(String value, long precision, int radix)	Constructs an apfloat from the specified string, precision and radix.
	Apfloat(BigDecimal value)	Creates an apfloat from a BigDecimal.
	Apfloat(BigDecimal value, long precision)	Creates an apfloat from a BigDecimal.
	Apfloat(BigInteger value)	Constructs an apfloat from a BigInteger.
	Apfloat(BigInteger value, long precision)	Constructs an apfloat from a BigInteger with the specified precision.
	Apfloat(BigInteger value, long precision, int radix)	Constructs an apfloat from a BigInteger with the specified precision and radix.
protected	Apfloat(ApfloatImpl impl)	Constructs an apfloat that is backed by the specified ApfloatImpl object.

Method Summary

Modifier and Type	Method	Description
Apfloat	add(Apfloat x)	Adds two apfloats.
byte	byteValue()	Returns the value of the this number as a byte.
Apint	ceil()	Ceiling function.
int	compareTo(Apfloat x)	Compare this apfloat to the specified apfloat.
Apfloat	divide(Apfloat x)	Divides two apfloats.
double	doubleValue()	Returns the value of the this number as a double.
long	equalDigits(Apfloat x)	Computes number of equal digits.
boolean	equals(Object obj)	Compares this object to the specified object.
float	floatValue()	Returns the value of the this number as a float.
Apint	floor()	Floor function.
void	formatTo(Formatter formatter, int flags, int width, int precision)	Formats the object using the provided formatter.
Apfloat	frac()	Returns the fractional part.
protected ApfloatImpl	getImpl(long precision)	Returns an ApfloatImpl representing the actual instance of this apfloat up to the requested precision.
int	hashCode()	Returns a hash code for this apfloat.
Apfloat	imag()	Imaginary part of this apfloat.
int	intValue()	Returns the value of the this number as an int.
boolean	isInteger()	Returns if this number has an integer value.
boolean	isShort()	Returns if this apfloat is "short".
long	longValue()	Returns the value of the this number as a long.
long	longValueExact()	Returns the value of the this number as a long, checking for lost information.
Apfloat	mod(Apfloat x)	Calculates the remainder when divided by an apfloat.
Apfloat	multiply(Apfloat x)	Multiplies two apfloats.
Apfloat	negate()	Negative value.
long	precision()	Returns the precision of this apfloat.
Apfloat	precision(long precision)	Returns an apfloat with the same value as this apfloat accurate to the specified precision.
boolean	preferCompare(Apfloat x)	Tests if the comparison with equals and compareTo should be done in the opposite order.
int	radix()	Radix of this apfloat.
Apfloat	real()	Real part of this apfloat.
long	scale()	Returns the scale of this apfloat.
short	shortValue()	Returns the value of the this number as a short.
int	signum()	Returns the signum function of this apfloat.
long	size()	Returns the size of this apfloat.
Apfloat	subtract(Apfloat x)	Subtracts two apfloats.
boolean	test(Apfloat x)	Tests two apfloat numbers for equality.
Apfloat	toRadix(int radix)	Convert this apfloat to the specified radix.
String	toString(boolean pretty)	Returns a string representation of this apfloat.
Apint	truncate()	Truncates fractional part.
void	writeTo(Writer out, boolean pretty)	Write a string representation of this apfloat to a Writer.

Methods inherited from class org.apfloat.Apcomplex

add, byteValueExact, conj, divide, equalDigits, intValueExact, isZero, multiply, shortValueExact, subtract, test, toString, writeTo

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

Apfloat

protected Apfloat()

Default constructor. To be used only by subclasses that overload all needed methods.

Apfloat

protected Apfloat(ApfloatImpl impl)

Constructs an apfloat that is backed by the specified ApfloatImpl object.

Parameters:

impl - The ApfloatImpl object backing this apfloat.

Apfloat

public Apfloat(String value)
        throws NumberFormatException,
ApfloatRuntimeException

Constructs an apfloat from the specified string. The default radix will be used.

The precision will be calculated from the number of digits specified in the string. For example:

"0.1" will have a precision of 1 digit.
"1.0" will have a precision of 2 digits.
"100" will have a precision of 3 digits.

Parameters:

value - The string representing the number.

Throws:

NumberFormatException - In case the number is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(String value,
 long precision)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified string and precision. The default radix will be used.

Parameters:

value - The string representing the number.

precision - The precision of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(String value,
 long precision,
 int radix)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified string, precision and radix.

Note that it's impossible to construct apfloats with a specified exponent and with radix >= 14, since the characters 'e' and 'E' will be treated as digits of the mantissa.

For example, in radix 10, "1e5" means the decimal number 100000. But in radix 16, "1e5" means the decimal number 485.

Parameters:

value - The string representing the number.

precision - The precision of the number.

radix - The radix of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(long value)
        throws NumberFormatException,
ApfloatRuntimeException

Constructs an apfloat from the specified long. The default radix will be used. The precision of the number will be Apcomplex.INFINITE.

Parameters:

value - The value of the number.

Throws:

NumberFormatException - In case the number is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(long value,
 long precision)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified long and precision. The default radix will be used.

Parameters:

value - The value of the number.

precision - The precision of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(long value,
 long precision,
 int radix)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified long, precision and radix.

Parameters:

value - The value of the number.

precision - The precision of the number.

radix - The radix of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(float value)
        throws NumberFormatException,
ApfloatRuntimeException

Constructs an apfloat from the specified float. The default radix will be used. The precision of the number will be the precision of a float in the default radix, for example in radix 10 the precision is 7 digits.

Parameters:

value - The value of the number.

Throws:

NumberFormatException - In case the number is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(float value,
 long precision)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified float and precision. The default radix will be used.

Note that the resulting apfloat won't accurately represent the given float value to more than the default precision of a float, for example in radix 10 the result is accurate to only 7 digits. The rest of the digits are unspecified even if a greater precision is specified.

Parameters:

value - The value of the number.

precision - The precision of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(float value,
 long precision,
 int radix)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified float, precision and radix.

Note that the resulting apfloat won't accurately represent the given float value to more than the default precision of a float, for example in radix 10 the result is accurate to only 7 digits. The rest of the digits are unspecified even if a greater precision is specified.

Parameters:

value - The value of the number.

precision - The precision of the number.

radix - The radix of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(double value)
        throws NumberFormatException,
ApfloatRuntimeException

Constructs an apfloat from the specified double. The default radix will be used. The precision of the number will be the precision of a double in the default radix, for example in radix 10 the precision is 16 digits.

Parameters:

value - The value of the number.

Throws:

NumberFormatException - In case the number is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(double value,
 long precision)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified double and precision. The default radix will be used.

Note that the resulting apfloat won't accurately represent the given double value to more than the default precision of a double, for example in radix 10 the result is accurate to only 16 digits. The rest of the digits are unspecified even if a greater precision is specified.

In particular, this constructor does not work the same way as the BigDecimal(double) constructor. If you want that kind of behavior then please use the Apfloat(BigDecimal, long) constructor.

Parameters:

value - The value of the number.

precision - The precision of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(double value,
 long precision,
 int radix)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from the specified double, precision and radix.

Note that the resulting apfloat won't accurately represent the given double value to more than the default precision of a double, for example in radix 10 the result is accurate to only 16 digits. The rest of the digits are unspecified even if a greater precision is specified.

In particular, this constructor does not work the same way as the BigDecimal(double) constructor. If you want that kind of behavior then please use the Apfloat(BigDecimal, long) constructor.

Parameters:

value - The value of the number.

precision - The precision of the number.

radix - The radix of the number.

Throws:

NumberFormatException - In case the number is invalid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(PushbackReader in)
        throws IOException,
NumberFormatException,
ApfloatRuntimeException

Reads an apfloat from a stream using default precision and radix. The stream needs to be a PushbackReader, as the first invalid character is pushed back to the stream.

Note that since only a pushback buffer of one character is used, the number read may still not be valid. For example, if the stream contains "-#" or "1.5e#" (here '#' is the first invalid character), the number is actually not valid, and only the character '#' would be put back to the stream.

The precision is determined similarly as in the Apfloat(String) constructor that is as the number of digits read from the stream.

Parameters:

in - The stream to read from

Throws:

IOException - If an I/O error occurs accessing the stream.

NumberFormatException - If the number is not valid.

ApfloatRuntimeException

Apfloat

public Apfloat(PushbackReader in,
 long precision)
        throws IOException,
NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Reads an apfloat from a stream using the specified precision. The default radix is used.

Parameters:

in - The stream to read from

precision - The precision of the number.

Throws:

IOException - If an I/O error occurs accessing the stream.

NumberFormatException - If the number is not valid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

See Also:

• Apfloat(PushbackReader)

Apfloat

public Apfloat(PushbackReader in,
 long precision,
 int radix)
        throws IOException,
NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Reads an apfloat from a stream using the specified precision and radix.

Parameters:

in - The stream to read from

precision - The precision of the number.

radix - The radix of the number.

Throws:

IOException - If an I/O error occurs accessing the stream.

NumberFormatException - If the number is not valid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

See Also:

• Apfloat(PushbackReader)

Apfloat

public Apfloat(BigInteger value)
        throws NumberFormatException,
ApfloatRuntimeException

Constructs an apfloat from a BigInteger. Precision will be Apcomplex.INFINITE and the default radix is used.

Parameters:

value - The value of the number.

Throws:

NumberFormatException - If the default radix is not valid.

ApfloatRuntimeException

Apfloat

public Apfloat(BigInteger value,
 long precision)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from a BigInteger with the specified precision. The default radix is used.

Parameters:

value - The value of the number.

precision - The precision of the number.

Throws:

NumberFormatException - If the default radix is not valid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(BigInteger value,
 long precision,
 int radix)
        throws NumberFormatException,
IllegalArgumentException,
ApfloatRuntimeException

Constructs an apfloat from a BigInteger with the specified precision and radix.

Parameters:

value - The value of the number.

precision - The precision of the number.

radix - The radix of the number.

Throws:

NumberFormatException - If the radix is not valid.

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Apfloat

public Apfloat(BigDecimal value)
        throws ApfloatRuntimeException

Creates an apfloat from a BigDecimal. An apfloat created this way will always have radix 10 regardless of the current default radix.

Parameters:

value - The value to use.

Throws:

ApfloatRuntimeException

Apfloat

public Apfloat(BigDecimal value,
 long precision)
        throws IllegalArgumentException,
ApfloatRuntimeException

Creates an apfloat from a BigDecimal. An apfloat created this way will always have radix 10 regardless of the current default radix.

Parameters:

value - The value to use.

precision - The precision to use, in decimal digits.

Throws:

IllegalArgumentException - In case the precision is invalid.

ApfloatRuntimeException

Method Details

radix

public int radix()

Radix of this apfloat.

Overrides:

radix in class Apcomplex

Returns:

Radix of this apfloat.

real

public Apfloat real()

Real part of this apfloat.

Overrides:

real in class Apcomplex

Returns:

this

imag

public Apfloat imag()

Imaginary part of this apfloat.

Overrides:

imag in class Apcomplex

Returns:

Apcomplex.ZERO

precision

public long precision()
               throws ApfloatRuntimeException

Returns the precision of this apfloat.

Overrides:

precision in class Apcomplex

Returns:

The precision of this apfloat in number of digits of the radix in which it's presented.

Throws:

ApfloatRuntimeException

precision

public Apfloat precision(long precision)
                  throws IllegalArgumentException,
ApfloatRuntimeException

Returns an apfloat with the same value as this apfloat accurate to the specified precision.

If the requested precision less than this number's current precision, the functionality is quite obvious: the precision is simply truncated, and e.g. comparison and equality checking will work as expected. Some rounding errors in e.g. addition and subtraction may still occur, as "invisible" trailing digits can remain in the number.

If the requested precision more than this number's current precision, the functionality is quite undefined: the digits up to this number's current precision are guaranteed to be the same, but the "new" digits are undefined: they may be zero, or they may be digits that have been previously discarded with a call to precision() with a smaller number of digits, or they may be something else, or any combination of these.

These limitations allow various performance optimizations to be made.

Overrides:

precision in class Apcomplex

Parameters:

precision - Precision of the new apfloat.

Returns:

An apfloat with the specified precision and same value as this apfloat.

Throws:

IllegalArgumentException - If precision is <= 0.

ApfloatRuntimeException

scale

public long scale()
           throws ApfloatRuntimeException

Returns the scale of this apfloat. The scale is defined here as

apfloat = signum * mantissa * radixscale

where 1/radix <= mantissa < 1. In other words, scale = floor(logradix(apfloat)) + 1.

For example, 1 has a scale of 1, and 100 has a scale of 3 (in radix 10). For integers, scale is equal to the number of digits in the apfloat.

Zero has a scale of -INFINITE.

Note that this definition of scale is different than in java.math.BigDecimal.

Overrides:

scale in class Apcomplex

Returns:

The exponent of this apfloat in number of digits of the radix in which it's presented.

Throws:

ApfloatRuntimeException

See Also:

• scale()

size

public long size()
          throws ApfloatRuntimeException

Returns the size of this apfloat. The size is defined here as

apfloat = signum * mantissa * radixscale and

mantissa = n / radixsize

where 1/radix <= mantissa < 1 and n is the smallest possible integer. In other words, the size is the number of significant digits in the mantissa (excluding leading and trailing zeros but including all zeros between the first and last nonzero digit). For example, 1 has a size of 1, and 100 has also a size of 1 (in radix 10). 11 has a size of 2, and 10001000 has a size of 5.

Zero has a size of 0.

Overrides:

size in class Apcomplex

Returns:

The number of digits in this number, from the most significant digit to the least significant nonzero digit, in the radix in which it's presented.

Throws:

ApfloatRuntimeException

Since:

1.6

See Also:

• size()

signum

public int signum()

Returns the signum function of this apfloat.

Returns:

-1, 0 or 1 as the value of this apfloat is negative, zero or positive, correspondingly.

isInteger

public boolean isInteger()
                  throws ApfloatRuntimeException

Returns if this number has an integer value. Note that this does not necessarily mean that this object is an instance of Apint. Neither does it mean that the precision is infinite.

Overrides:

isInteger in class Apcomplex

Returns:

If this number's value is an integer.

Throws:

ApfloatRuntimeException

Since:

1.9.0

isShort

public boolean isShort()
                throws ApfloatRuntimeException

Returns if this apfloat is "short". In practice an apfloat is "short" if its mantissa fits in one machine word. If the apfloat is "short", some algorithms can be performed faster.

For example, division by a "short" apfloat requires only a single pass through the data, but that algorithm can't be used for divisors that aren't "short", where calculating an inverse root is required instead.

The return value of this method is implementation dependent.

Returns:

true if the apfloat is "short", false if not.

Throws:

ApfloatRuntimeException

negate

public Apfloat negate()
               throws ApfloatRuntimeException

Negative value.

Overrides:

negate in class Apcomplex

Returns:

-this.

Throws:

ApfloatRuntimeException

Since:

1.1

add

public Apfloat add(Apfloat x)
            throws ApfloatRuntimeException

Adds two apfloats.

Parameters:

x - The number to be added to this number.

Returns:

this + x.

Throws:

ApfloatRuntimeException

subtract

public Apfloat subtract(Apfloat x)
                 throws ApfloatRuntimeException

Subtracts two apfloats.

Parameters:

x - The number to be subtracted from this number.

Returns:

this - x.

Throws:

ApfloatRuntimeException

multiply

public Apfloat multiply(Apfloat x)
                 throws ApfloatRuntimeException

Multiplies two apfloats.

Parameters:

x - The number to be multiplied by this number.

Returns:

this * x.

Throws:

ApfloatRuntimeException

divide

public Apfloat divide(Apfloat x)
               throws ArithmeticException,
ApfloatRuntimeException

Divides two apfloats.

Parameters:

x - The number by which this number is to be divided.

Returns:

this / x.

Throws:

ArithmeticException - In case the divisor is zero.

ApfloatRuntimeException

mod

public Apfloat mod(Apfloat x)
            throws ApfloatRuntimeException

Calculates the remainder when divided by an apfloat. The result has the same sign as this number. If x is zero, then zero is returned.

Parameters:

x - The number that is used as the divisor in the remainder calculation.

Returns:

this % x.

Throws:

ApfloatRuntimeException

Since:

1.2

See Also:

• ApfloatMath.fmod(Apfloat,Apfloat)

floor

public Apint floor()
            throws ApfloatRuntimeException

Floor function. Returns the largest (closest to positive infinity) value that is not greater than this apfloat and is equal to a mathematical integer.

Returns:

This apfloat rounded towards negative infinity.

Throws:

ApfloatRuntimeException

ceil

public Apint ceil()
           throws ApfloatRuntimeException

Ceiling function. Returns the smallest (closest to negative infinity) value that is not less than this apfloat and is equal to a mathematical integer.

Returns:

This apfloat rounded towards positive infinity.

Throws:

ApfloatRuntimeException

truncate

public Apint truncate()
               throws ApfloatRuntimeException

Truncates fractional part.

Returns:

This apfloat rounded towards zero.

Throws:

ApfloatRuntimeException

frac

public Apfloat frac()
             throws ApfloatRuntimeException

Returns the fractional part. The fractional part is always 0 <= abs(frac()) < 1. The fractional part has the same sign as the number. For the fractional and integer parts, this always holds:

x = x.truncate() + x.frac()

Returns:

The fractional part of this apfloat.

Throws:

ApfloatRuntimeException

Since:

1.7.0

doubleValue

public double doubleValue()

Returns the value of the this number as a double. If the number is too big to fit in a double, Double.POSITIVE_INFINITY or Double.NEGATIVE_INFINITY is returned.

Overrides:

doubleValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type double.

See Also:

• doubleValue()

floatValue

public float floatValue()

Returns the value of the this number as a float. If the number is too big to fit in a float, Float.POSITIVE_INFINITY or Float.NEGATIVE_INFINITY is returned.

Overrides:

floatValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type float.

See Also:

• floatValue()

byteValue

public byte byteValue()

Returns the value of the this number as a byte. If the number is too big to fit in a byte, Byte.MIN_VALUE or Byte.MAX_VALUE is returned.

Overrides:

byteValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type byte.

See Also:

• byteValue()

shortValue

public short shortValue()

Returns the value of the this number as a short. If the number is too big to fit in a short, Short.MIN_VALUE or Short.MAX_VALUE is returned.

Overrides:

shortValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type short.

See Also:

• shortValue()

intValue

public int intValue()

Returns the value of the this number as an int. If the number is too big to fit in an int, Integer.MIN_VALUE or Integer.MAX_VALUE is returned.

Overrides:

intValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type int.

See Also:

• intValue()

longValue

public long longValue()

Returns the value of the this number as a long. If the number is too big to fit in a long, Long.MIN_VALUE or Long.MAX_VALUE is returned.

Overrides:

longValue in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type long.

See Also:

• longValue()

longValueExact

public long longValueExact()
                    throws ArithmeticException

Description copied from class: Apcomplex

Returns the value of the this number as a long, checking for lost information. If the value of this number is out of the range of the long type, then an ArithmeticException is thrown.

Overrides:

longValueExact in class Apcomplex

Returns:

The numeric value represented by this object after conversion to type long.

Throws:

ArithmeticException - If the value of this will not exactly fit in a long or has a nonzero fractional part.

equalDigits

public long equalDigits(Apfloat x)
                 throws ApfloatRuntimeException

Computes number of equal digits.

Compares the digits of the numbers starting from the most significant digits. The exponent and sign are taken into consideration, so if either one doesn't match, the numbers are considered to have zero equal digits.

For example, the numbers 12345 and 123456 have zero matching digits, and the numbers 12345 and 12355 have three matching digits.

The result of this method is roughly equal to Math.min(scale(), x.scale()) - subtract(x).scale() but it typically is a lot more efficient to execute.

Parameters:

x - Number to compare with.

Returns:

Number of matching digits in the radix in which the numbers are presented.

Throws:

ApfloatRuntimeException

toRadix

public Apfloat toRadix(int radix)
                throws NumberFormatException,
ApfloatRuntimeException

Convert this apfloat to the specified radix.

Overrides:

toRadix in class Apcomplex

Parameters:

radix - The radix.

Returns:

This number in the specified radix.

Throws:

NumberFormatException - If the radix is invalid.

ApfloatRuntimeException

Since:

1.2

compareTo

public int compareTo(Apfloat x)

Compare this apfloat to the specified apfloat.

Note: if two apfloats are compared where one number doesn't have enough precise digits, the mantissa is assumed to contain zeros. For example:

 Apfloat x = new Apfloat("0.12", 2);
 Apfloat y = new Apfloat("0.12345", 5);
 

Now x.compareTo(y) < 0 because x is assumed to be 0.12000.

However, new Apfloat("0.12", 2) and new Apfloat("0.12", 5) would be considered equal.

Specified by:

compareTo in interface Comparable<Apfloat>

Parameters:

x - Apfloat to which this apfloat is to be compared.

Returns:

-1, 0 or 1 as this apfloat is numerically less than, equal to, or greater than x.

preferCompare

public boolean preferCompare(Apfloat x)

Tests if the comparison with equals and compareTo should be done in the opposite order.

Implementations should avoid infinite recursion.

Parameters:

x - The number to compare to.

Returns:

true if this object should invoke x.equals(this) and -x.compareTo(this) instead of comparing normally.

Since:

1.7.0

equals

public boolean equals(Object obj)

Compares this object to the specified object.

Note: if two apfloats are compared where one number doesn't have enough precise digits, the mantissa is assumed to contain zeros. See compareTo(Apfloat).

Overrides:

equals in class Apcomplex

Parameters:

obj - The object to compare with.

Returns:

true if the objects are equal; false otherwise.

test

public boolean test(Apfloat x)
             throws ApfloatRuntimeException

Tests two apfloat numbers for equality. Returns false if the numbers are definitely known to be not equal. If true is returned, equality is unknown and should be verified by calling equals(Object). This method is usually significantly faster than calling equals(Object).

Parameters:

x - The number to test against.

Returns:

false if the numbers are definitely not equal, true if unknown.

Throws:

ApfloatRuntimeException

Since:

1.10.0

hashCode

public int hashCode()

Returns a hash code for this apfloat.

Overrides:

hashCode in class Apcomplex

Returns:

The hash code value for this object.

toString

public String toString(boolean pretty)
                throws ApfloatRuntimeException

Returns a string representation of this apfloat.

Overrides:

toString in class Apcomplex

Parameters:

pretty - true to use a fixed-point notation, false to use an exponential notation.

Returns:

A string representing this object.

Throws:

ApfloatRuntimeException

writeTo

public void writeTo(Writer out,
 boolean pretty)
             throws IOException,
ApfloatRuntimeException

Write a string representation of this apfloat to a Writer.

Overrides:

writeTo in class Apcomplex

Parameters:

out - The output Writer.

pretty - true to use a fixed-point notation, false to use an exponential notation.

Throws:

IOException - In case of I/O error writing to the stream.

ApfloatRuntimeException

formatTo

public void formatTo(Formatter formatter,
 int flags,
 int width,
 int precision)

Formats the object using the provided formatter.

The format specifiers affect the output as follows:

• By default, the exponential notation is used.
• If the alternate format is specified ('#'), then the fixed-point notation is used.
• Width is the minimum number of characters output. Any padding is done using spaces. Padding is on the left by default.
• If the '-' flag is specified, then the padding will be on the right.
• The precision is the number of significant digts output. If the precision of the number exceeds the number of characters output, the rounding mode for output is undefined.

The decimal separator will be localized if the formatter specifies a locale. The digits will be localized also, but only if the radix is less than or equal to 10.

Specified by:

formatTo in interface Formattable

Overrides:

formatTo in class Apcomplex

Parameters:

formatter - The formatter.

flags - The flags to modify the output format.

width - The minimum number of characters to be written to the output, or -1 for no minimum.

precision - The maximum number of characters to be written to the output, or -1 for no maximum.

Since:

1.3

See Also:

• formatTo(Formatter,int,int,int)

getImpl

protected ApfloatImpl getImpl(long precision)
                       throws ApfloatRuntimeException

Returns an ApfloatImpl representing the actual instance of this apfloat up to the requested precision.

For apfloats this is simply the underlying ApfloatImpl, but e.g. the Aprational class implements this so that it only returns an approximation of the rational number.

Parameters:

precision - Precision of the ApfloatImpl that is needed.

Returns:

An ApfloatImpl representing this object to the requested precision.

Throws:

ApfloatRuntimeException