Modifier and Type | Field and Description |
---|---|
static double |
EPSILON
Smallest positive number such that 1 - EPSILON is not numerically equal to 1.
|
static double |
SAFE_MIN
Safe minimum, such that 1 / SAFE_MIN does not overflow.
|
static double |
TWO_PI
2 π.
|
Modifier and Type | Method and Description |
---|---|
static int |
addAndCheck(int x,
int y)
Add two integers, checking for overflow.
|
static long |
addAndCheck(long a,
long b)
Add two long integers, checking for overflow.
|
static long |
binomialCoefficient(int n,
int k)
Returns an exact representation of the
Binomial Coefficient, "
n choose k ", the number of k -element
subsets that can be selected from an n -element set. |
static double |
binomialCoefficientDouble(int n,
int k)
Returns a
double representation of the
Binomial Coefficient, "n choose k ", the number of k -element
subsets that can be selected from an n -element set. |
static double |
binomialCoefficientLog(int n,
int k)
Returns the natural
log of the
Binomial Coefficient, "n choose k ", the number of k -element
subsets that can be selected from an n -element set. |
static void |
checkOrder(double[] val,
int dir,
boolean strict)
Checks that the given array is sorted.
|
static int |
compareTo(double x,
double y,
double eps)
Compares two numbers given some amount of allowed error.
|
static double |
cosh(double x)
Returns the hyperbolic
cosine of x.
|
static double |
distance(double[] p1,
double[] p2)
Calculates the L2 (Euclidean) distance between two points.
|
static double |
distance(int[] p1,
int[] p2)
Calculates the L2 (Euclidean) distance between two points.
|
static double |
distance1(double[] p1,
double[] p2)
Calculates the L1 (sum of abs) distance between two points.
|
static int |
distance1(int[] p1,
int[] p2)
Calculates the L1 (sum of abs) distance between two points.
|
static double |
distanceInf(double[] p1,
double[] p2)
Calculates the L∞ (max of abs) distance between two points.
|
static int |
distanceInf(int[] p1,
int[] p2)
Calculates the L∞ (max of abs) distance between two points.
|
static boolean |
equals(double[] x,
double[] y)
Returns true iff both arguments are null or have same dimensions and all their elements are
equals |
static boolean |
equals(double x,
double y)
Returns true iff both arguments are NaN or neither is NaN and they are equal
|
static boolean |
equals(double x,
double y,
double eps)
Returns true iff both arguments are equal or within the range of allowed error (inclusive).
|
static boolean |
equals(double x,
double y,
int maxUlps)
Returns true iff both arguments are equal or within the range of allowed error (inclusive).
|
static long |
factorial(int n)
Returns n!.
|
static double |
factorialDouble(int n)
Returns n!.
|
static double |
factorialLog(int n)
Returns the natural logarithm of n!.
|
static int |
gcd(int p,
int q)
Gets the greatest common divisor of the absolute value of two numbers, using the "binary
gcd" method which avoids division and modulo operations.
|
static long |
gcd(long p,
long q)
Gets the greatest common divisor of the absolute value of two numbers, using the "binary
gcd" method which avoids division and modulo operations.
|
static int |
hash(double value)
Returns an integer hash code representing the given double value.
|
static int |
hash(double[] value)
Returns an integer hash code representing the given double array.
|
static byte |
indicator(byte x)
For a byte value x, this method returns (byte)(+1) if x >= 0 and (byte)(-1) if x < 0.
|
static double |
indicator(double x)
For a double precision value x, this method returns +1.0 if x >= 0 and -1.0 if x < 0.
|
static float |
indicator(float x)
For a float value x, this method returns +1.0F if x >= 0 and -1.0F if x < 0.
|
static int |
indicator(int x)
For an int value x, this method returns +1 if x >= 0 and -1 if x < 0.
|
static long |
indicator(long x)
For a long value x, this method returns +1L if x >= 0 and -1L if x < 0.
|
static short |
indicator(short x)
For a short value x, this method returns (short)(+1) if x >= 0 and (short)(-1) if x < 0.
|
static int |
lcm(int a,
int b)
Returns the least common multiple of the absolute value of two numbers, using the formula
lcm(a,b) = (a / gcd(a,b)) * b . |
static long |
lcm(long a,
long b)
Returns the least common multiple of the absolute value of two numbers, using the formula
lcm(a,b) = (a / gcd(a,b)) * b . |
static double |
log(double base,
double x)
|
static int |
mulAndCheck(int x,
int y)
Multiply two integers, checking for overflow.
|
static long |
mulAndCheck(long a,
long b)
Multiply two long integers, checking for overflow.
|
static double |
nextAfter(double d,
double direction)
Get the next machine representable number after a number, moving in the direction of another
number.
|
static double |
normalizeAngle(double a,
double center)
Normalize an angle in a 2&pi wide interval around a center value.
|
static double[] |
normalizeArray(double[] values,
double normalizedSum)
Normalizes an array to make it sum to a specified value.
|
static BigInteger |
pow(BigInteger k,
BigInteger e)
Raise a BigInteger to a BigInteger power.
|
static BigInteger |
pow(BigInteger k,
int e)
Raise a BigInteger to an int power.
|
static BigInteger |
pow(BigInteger k,
long e)
Raise a BigInteger to a long power.
|
static int |
pow(int k,
int e)
Raise an int to an int power.
|
static int |
pow(int k,
long e)
Raise an int to a long power.
|
static long |
pow(long k,
int e)
Raise a long to an int power.
|
static long |
pow(long k,
long e)
Raise a long to a long power.
|
static double |
round(double x,
int scale)
Round the given value to the specified number of decimal places.
|
static double |
round(double x,
int scale,
int roundingMethod)
Round the given value to the specified number of decimal places.
|
static float |
round(float x,
int scale)
Round the given value to the specified number of decimal places.
|
static float |
round(float x,
int scale,
int roundingMethod)
Round the given value to the specified number of decimal places.
|
static double |
scalb(double d,
int scaleFactor)
Scale a number by 2scaleFactor.
|
static byte |
sign(byte x)
Returns the sign for byte value
x . |
static double |
sign(double x)
Returns the sign for double precision
x . |
static float |
sign(float x)
Returns the sign for float value
x . |
static int |
sign(int x)
Returns the sign for int value
x . |
static long |
sign(long x)
Returns the sign for long value
x . |
static short |
sign(short x)
Returns the sign for short value
x . |
static double |
sinh(double x)
Returns the hyperbolic sine
of x.
|
static int |
subAndCheck(int x,
int y)
Subtract two integers, checking for overflow.
|
static long |
subAndCheck(long a,
long b)
Subtract two long integers, checking for overflow.
|
public static final double EPSILON
public static final double SAFE_MIN
In IEEE 754 arithmetic, this is also the smallest normalized number 2-1022.
public static final double TWO_PI
public static int addAndCheck(int x, int y)
x
- an addendy
- an addendx+y
ArithmeticException
- if the result can not be represented as an intpublic static long addAndCheck(long a, long b)
a
- an addendb
- an addenda+b
ArithmeticException
- if the result can not be represented as an longpublic static long binomialCoefficient(int n, int k)
n choose k
", the number of k
-element
subsets that can be selected from an n
-element set. Preconditions:
0 <= k <= n
(otherwise
IllegalArgumentException
is thrown)long
. The largest value of n
for which all coefficients are
< Long.MAX_VALUE
is 66. If the computed value exceeds
Long.MAX_VALUE
an ArithMeticException
is thrown.n
- the size of the setk
- the size of the subsets to be countedn choose k
IllegalArgumentException
- if preconditions are not met.ArithmeticException
- if the result is too large to be represented by a long
integer.public static double binomialCoefficientDouble(int n, int k)
double
representation of the
Binomial Coefficient, "n choose k
", the number of k
-element
subsets that can be selected from an n
-element set. Preconditions:
0 <= k <= n
(otherwise
IllegalArgumentException
is thrown)double
. The largest value of n
for which all coefficients
are < Double.MAX_VALUE is 1029. If the computed value exceeds Double.MAX_VALUE,
Double.POSITIVE_INFINITY is returnedn
- the size of the setk
- the size of the subsets to be countedn choose k
IllegalArgumentException
- if preconditions are not met.public static double binomialCoefficientLog(int n, int k)
log
of the
Binomial Coefficient, "n choose k
", the number of k
-element
subsets that can be selected from an n
-element set. Preconditions:
0 <= k <= n
(otherwise
IllegalArgumentException
is thrown)n
- the size of the setk
- the size of the subsets to be countedn choose k
IllegalArgumentException
- if preconditions are not met.public static int compareTo(double x, double y, double eps)
x
- the first numbery
- the second numbereps
- the amount of error to allow when checking for equalityequals(x, y, eps)
equals(x, y, eps)
&& x < yequals(x, y, eps)
&& x >
ypublic static double cosh(double x)
x
- double value for which to find the hyperbolic cosinepublic static boolean equals(double x, double y)
x
- first valuey
- second valuepublic static boolean equals(double x, double y, double eps)
Two NaNs are considered equals, as are two infinities with same sign.
x
- first valuey
- second valueeps
- the amount of absolute error to allowpublic static boolean equals(double x, double y, int maxUlps)
x
- first valuey
- second valuemaxUlps
- (maxUlps - 1)
is the number of floating point values between x
and y
.true
if there are less than maxUlps
floating point values between
x
and y
public static boolean equals(double[] x, double[] y)
equals
x
- first arrayy
- second arraypublic static long factorial(int n)
n
Factorial, the product of the numbers 1,...,n
. Preconditions:
n >= 0
(otherwise
IllegalArgumentException
is thrown)long
. The largest value of n
for which n!
<
Long.MAX_VALUE is 20. If the computed value exceeds Long.MAX_VALUE
an
ArithMeticException
is thrown.n
- argumentn!
ArithmeticException
- if the result is too large to be represented by a long
integer.IllegalArgumentException
- if n < 0public static double factorialDouble(int n)
n
Factorial, the product of the numbers 1,...,n
as a double
. Preconditions:
n >= 0
(otherwise
IllegalArgumentException
is thrown)double
. The largest value of n
for which n!
<
Double.MAX_VALUE is 170. If the computed value exceeds Double.MAX_VALUE,
Double.POSITIVE_INFINITY is returnedn
- argumentn!
IllegalArgumentException
- if n < 0public static double factorialLog(int n)
Preconditions:
n >=
0
(otherwise IllegalArgumentException
is thrown)n
- argumentn!
IllegalArgumentException
- if preconditions are not met.public static int gcd(int p, int q)
Gets the greatest common divisor of the absolute value of two numbers, using the "binary gcd" method which avoids division and modulo operations. See Knuth 4.5.2 algorithm B. This algorithm is due to Josef Stein (1961).
Special cases:gcd(Integer.MIN_VALUE, Integer.MIN_VALUE)
, gcd(Integer.MIN_VALUE,
0)
and gcd(0, Integer.MIN_VALUE)
throw an ArithmeticException
,
because the result would be 2^31, which is too large for an int value.gcd(x, x)
, gcd(0, x)
and gcd(x, 0)
is the absolute
value of x
, except for the special cases above. gcd(0,
0)
is the only one which returns 0
.p
- any numberq
- any numberArithmeticException
- if the result cannot be represented as a nonnegative int valuepublic static long gcd(long p, long q)
Gets the greatest common divisor of the absolute value of two numbers, using the "binary gcd" method which avoids division and modulo operations. See Knuth 4.5.2 algorithm B. This algorithm is due to Josef Stein (1961).
Special cases:gcd(Long.MIN_VALUE, Long.MIN_VALUE)
, gcd(Long.MIN_VALUE, 0L)
and
gcd(0L, Long.MIN_VALUE)
throw an ArithmeticException
, because the
result would be 2^63, which is too large for a long value.gcd(x, x)
, gcd(0L, x)
and gcd(x, 0L)
is the absolute
value of x
, except for the special cases above. gcd(0L,
0L)
is the only one which returns 0L
.p
- any numberq
- any numberArithmeticException
- if the result cannot be represented as a nonnegative long valuepublic static int hash(double value)
value
- the value to be hashedpublic static int hash(double[] value)
value
- the value to be hashed (may be null)public static byte indicator(byte x)
x
- the value, a bytepublic static double indicator(double x)
NaN
if x
is NaN
.x
- the value, a doublepublic static float indicator(float x)
NaN
if x
is NaN
.x
- the value, a floatpublic static int indicator(int x)
x
- the value, an intpublic static long indicator(long x)
x
- the value, a longpublic static short indicator(short x)
x
- the value, a shortpublic static int lcm(int a, int b)
Returns the least common multiple of the absolute value of two numbers, using the formula
lcm(a,b) = (a / gcd(a,b)) * b
.
lcm(Integer.MIN_VALUE, n)
and lcm(n, Integer.MIN_VALUE)
, where
abs(n)
is a power of 2, throw an ArithmeticException
, because the
result would be 2^31, which is too large for an int value.lcm(0, x)
and lcm(x, 0)
is 0
for any x
.
a
- any numberb
- any numberArithmeticException
- if the result cannot be represented as a nonnegative int valuepublic static long lcm(long a, long b)
Returns the least common multiple of the absolute value of two numbers, using the formula
lcm(a,b) = (a / gcd(a,b)) * b
.
lcm(Long.MIN_VALUE, n)
and lcm(n, Long.MIN_VALUE)
, where
abs(n)
is a power of 2, throw an ArithmeticException
, because the
result would be 2^63, which is too large for an int value.lcm(0L, x)
and lcm(x, 0L)
is 0L
for any
x
. a
- any numberb
- any numberArithmeticException
- if the result cannot be represented as a nonnegative long valuepublic static double log(double base, double x)
Returns the logarithm for base
b
of x
.
Returns NaN
if either argument is
negative. If
base
is 0 and x
is positive, 0 is returned. If
base
is positive and x
is 0, Double.NEGATIVE_INFINITY
is returned. If both arguments are 0, the result is NaN
.
base
- the base of the logarithm, must be greater than 0x
- argument, must be greater than 0public static int mulAndCheck(int x, int y)
x
- a factory
- a factorx*y
ArithmeticException
- if the result can not be represented as an intpublic static long mulAndCheck(long a, long b)
a
- first valueb
- second valuea * b
ArithmeticException
- if the result can not be represented as an longpublic static double nextAfter(double d, double direction)
If direction
is greater than or equal tod
, the smallest
machine representable number strictly greater than d
is returned; otherwise the
largest representable number strictly less than d
is returned.
If
d
is NaN or Infinite, it is returned unchanged.
d
- base numberdirection
- (the only important thing is whether direction is greater or smaller than
d)public static double scalb(double d, int scaleFactor)
If d
is 0 or NaN or Infinite, it
is returned unchanged.
d
- base numberscaleFactor
- power of two by which d sould be multipliedpublic static double normalizeAngle(double a, double center)
This method has three main uses:
a =
MathUtils.normalizeAngle(a, Math.PI);
a = MathUtils.normalizeAngle(a, 0.0);
angle = MathUtils.normalizeAngle(end,
start) - start;
Note that due to numerical accuracy and since π cannot be represented exactly, the result interval is closed, it cannot be half-closed as would be more satisfactory in a purely mathematical view.
a
- angle to normalizecenter
- center of the desired 2π interval for the resultpublic static double[] normalizeArray(double[] values, double normalizedSum) throws ArithmeticException, IllegalArgumentException
Normalizes an array to make it sum to a specified value. Returns the result of the transformation
x |-> x * normalizedSum / sumapplied to each non-NaN element x of the input array, where sum is the sum of the non-NaN entries in the input array.
Throws IllegalArgumentException if normalizedSum
is infinite or NaN and
ArithmeticException if the input array contains any infinite elements or sums to 0
Ignores (i.e., copies unchanged to the output array) NaNs in the input array.
values
- input array to be normalizednormalizedSum
- target sum for the normalized arrayArithmeticException
- if the input array contains infinite elements or sums to
zeroIllegalArgumentException
- if the target sum is infinite or NaNpublic static double round(double x, int scale)
BigDecimal.ROUND_HALF_UP
method.x
- the value to round.scale
- the number of digits to the right of the decimal point.public static double round(double x, int scale, int roundingMethod)
BigDecimal
.x
- the value to round.scale
- the number of digits to the right of the decimal point.roundingMethod
- the rounding method as defined in BigDecimal
.public static float round(float x, int scale)
BigDecimal.ROUND_HALF_UP
method.x
- the value to round.scale
- the number of digits to the right of the decimal point.public static float round(float x, int scale, int roundingMethod)
BigDecimal
.x
- the value to round.scale
- the number of digits to the right of the decimal point.roundingMethod
- the rounding method as defined in BigDecimal
.public static byte sign(byte x)
x
. For a byte value x, this method returns (byte)(+1) if x > 0, (byte)(0) if x = 0, and (byte)(-1) if x < 0.
x
- the value, a bytepublic static double sign(double x)
x
. For a double value x
, this method returns +1.0
if x > 0
, 0.0
if x = 0.0
, and -1.0
if
x < 0
. Returns NaN
if x
is NaN
.
x
- the value, a doublepublic static float sign(float x)
x
. For a float value x, this method returns +1.0F if x > 0, 0.0F if x =
0.0F, and -1.0F if x < 0. Returns NaN
if x
is
NaN
.
x
- the value, a floatpublic static int sign(int x)
x
. For an int value x, this method returns +1 if x > 0, 0 if x = 0, and -1 if x < 0.
x
- the value, an intpublic static long sign(long x)
x
. For a long value x, this method returns +1L if x > 0, 0L if x = 0, and -1L if x < 0.
x
- the value, a longpublic static short sign(short x)
x
. For a short value x, this method returns (short)(+1) if x > 0, (short)(0) if x = 0, and (short)(-1) if x < 0.
x
- the value, a shortpublic static double sinh(double x)
x
- double value for which to find the hyperbolic sinepublic static int subAndCheck(int x, int y)
x
- the minuendy
- the subtrahendx-y
ArithmeticException
- if the result can not be represented as an intpublic static long subAndCheck(long a, long b)
a
- first valueb
- second valuea-b
ArithmeticException
- if the result can not be represented as an longpublic static int pow(int k, int e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static int pow(int k, long e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static long pow(long k, int e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static long pow(long k, long e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static BigInteger pow(BigInteger k, int e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static BigInteger pow(BigInteger k, long e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static BigInteger pow(BigInteger k, BigInteger e) throws IllegalArgumentException
k
- number to raisee
- exponent (must be positive or null)IllegalArgumentException
- if e is negativepublic static double distance1(double[] p1, double[] p2)
p1
- the first pointp2
- the second pointpublic static int distance1(int[] p1, int[] p2)
p1
- the first pointp2
- the second pointpublic static double distance(double[] p1, double[] p2)
p1
- the first pointp2
- the second pointpublic static double distance(int[] p1, int[] p2)
p1
- the first pointp2
- the second pointpublic static double distanceInf(double[] p1, double[] p2)
p1
- the first pointp2
- the second pointpublic static int distanceInf(int[] p1, int[] p2)
p1
- the first pointp2
- the second pointpublic static void checkOrder(double[] val, int dir, boolean strict)
val
- Valuesdir
- Order direction (-1 for decreasing, 1 for increasing)strict
- Whether the order should be strictIllegalArgumentException
- if the array is not sorted.Copyright © GigaSpaces.