cern.jet.math
Class IntFunctions

java.lang.Object
  cern.jet.math.IntFunctions

public class IntFunctions

extends Object

Integer Function objects to be passed to generic methods. Same as Functions except operating on integers.

For aliasing see intFunctions.

Version:

1.0, 09/24/99

Field Summary

static IntFunction	abs Function that returns Math.abs(a) == (a < 0) ? -a : a.
static IntIntFunction	and Function that returns a & b.
static IntIntFunction	compare Function that returns a < b ? -1 : a > b ? 1 : 0.
static IntFunction	dec Function that returns a--.
static IntIntFunction	div Function that returns a / b.
static IntIntFunction	equals Function that returns a == b ? 1 : 0.
static IntFunction	factorial Function that returns (int) Arithmetic.factorial(a).
static IntFunction	identity Function that returns its argument.
static IntFunction	inc Function that returns a++.
static IntFunctions	intFunctions Little trick to allow for "aliasing", that is, renaming this class.
static IntIntProcedure	isEqual Function that returns a == b.
static IntIntProcedure	isGreater Function that returns a > b.
static IntIntProcedure	isLess Function that returns a < b.
static IntIntFunction	max Function that returns Math.max(a,b).
static IntIntFunction	min Function that returns Math.min(a,b).
static IntIntFunction	minus Function that returns a - b.
static IntIntFunction	mod Function that returns a % b.
static IntIntFunction	mult Function that returns a * b.
static IntFunction	neg Function that returns -a.
static IntFunction	not Function that returns ~a.
static IntIntFunction	or Function that returns a | b.
static IntIntFunction	plus Function that returns a + b.
static IntIntFunction	pow Function that returns (int) Math.pow(a,b).
static IntIntFunction	shiftLeft Function that returns a << b.
static IntIntFunction	shiftRightSigned Function that returns a >> b.
static IntIntFunction	shiftRightUnsigned Function that returns a >>> b.
static IntFunction	sign Function that returns a < 0 ? -1 : a > 0 ? 1 : 0.
static IntFunction	square Function that returns a * a.
static IntIntFunction	xor Function that returns a ^ b.

Method Summary

static IntFunction	and(int b) Constructs a function that returns a & b.
static IntFunction	between(int from, int to) Constructs a function that returns (from<=a && a<=to) ? 1 : 0.
static IntFunction	bindArg1(IntIntFunction function, int c) Constructs a unary function from a binary function with the first operand (argument) fixed to the given constant c.
static IntFunction	bindArg2(IntIntFunction function, int c) Constructs a unary function from a binary function with the second operand (argument) fixed to the given constant c.
static IntFunction	chain(IntFunction g, IntFunction h) Constructs the function g( h(a) ).
static IntIntFunction	chain(IntFunction g, IntIntFunction h) Constructs the function g( h(a,b) ).
static IntIntFunction	chain(IntIntFunction f, IntFunction g, IntFunction h) Constructs the function f( g(a), h(b) ).
static IntFunction	compare(int b) Constructs a function that returns a < b ? -1 : a > b ? 1 : 0.
static IntFunction	constant(int c) Constructs a function that returns the constant c.
static IntFunction	div(int b) Constructs a function that returns a / b.
static IntFunction	equals(int b) Constructs a function that returns a == b ? 1 : 0.
static IntProcedure	isBetween(int from, int to) Constructs a function that returns from<=a && a<=to.
static IntProcedure	isEqual(int b) Constructs a function that returns a == b.
static IntProcedure	isGreater(int b) Constructs a function that returns a > b.
static IntProcedure	isLess(int b) Constructs a function that returns a < b.
static IntFunction	max(int b) Constructs a function that returns Math.max(a,b).
static IntFunction	min(int b) Constructs a function that returns Math.min(a,b).
static IntFunction	minus(int b) Constructs a function that returns a - b.
static IntFunction	mod(int b) Constructs a function that returns a % b.
static IntFunction	mult(int b) Constructs a function that returns a * b.
static IntFunction	or(int b) Constructs a function that returns a | b.
static IntFunction	plus(int b) Constructs a function that returns a + b.
static IntFunction	pow(int b) Constructs a function that returns (int) Math.pow(a,b).
static IntFunction	random() Constructs a function that returns a 32 bit uniformly distributed random number in the closed interval [Integer.MIN_VALUE,Integer.MAX_VALUE] (including Integer.MIN_VALUE and Integer.MAX_VALUE).
static IntFunction	shiftLeft(int b) Constructs a function that returns a << b.
static IntFunction	shiftRightSigned(int b) Constructs a function that returns a >> b.
static IntFunction	shiftRightUnsigned(int b) Constructs a function that returns a >>> b.
static IntIntFunction	swapArgs(IntIntFunction function) Constructs a function that returns function.apply(b,a), i.e.
static IntFunction	xor(int b) Constructs a function that returns a | b.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

intFunctions

public static final IntFunctions intFunctions

Little trick to allow for "aliasing", that is, renaming this class. Writing code like

IntFunctions.chain(IntFunctions.plus,IntFunctions.mult(3),IntFunctions.chain(IntFunctions.square,IntFunctions.div(2)));

is a bit awkward, to say the least. Using the aliasing you can instead write

IntFunctions F = IntFunctions.intFunctions;
F.chain(F.plus,F.mult(3),F.chain(F.square,F.div(2)));

abs

public static final IntFunction abs

Function that returns Math.abs(a) == (a < 0) ? -a : a.

dec

public static final IntFunction dec

Function that returns a--.

factorial

public static final IntFunction factorial

Function that returns (int) Arithmetic.factorial(a).

identity

public static final IntFunction identity

Function that returns its argument.

inc

public static final IntFunction inc

Function that returns a++.

neg

public static final IntFunction neg

Function that returns -a.

not

public static final IntFunction not

Function that returns ~a.

sign

public static final IntFunction sign

Function that returns a < 0 ? -1 : a > 0 ? 1 : 0.

square

public static final IntFunction square

Function that returns a * a.

and

public static final IntIntFunction and

Function that returns a & b.

compare

public static final IntIntFunction compare

Function that returns a < b ? -1 : a > b ? 1 : 0.

div

public static final IntIntFunction div

Function that returns a / b.

equals

public static final IntIntFunction equals

Function that returns a == b ? 1 : 0.

isEqual

public static final IntIntProcedure isEqual

Function that returns a == b.

isLess

public static final IntIntProcedure isLess

Function that returns a < b.

isGreater

public static final IntIntProcedure isGreater

Function that returns a > b.

max

public static final IntIntFunction max

Function that returns Math.max(a,b).

min

public static final IntIntFunction min

Function that returns Math.min(a,b).

minus

public static final IntIntFunction minus

Function that returns a - b.

mod

public static final IntIntFunction mod

Function that returns a % b.

mult

public static final IntIntFunction mult

Function that returns a * b.

or

public static final IntIntFunction or

Function that returns a | b.

plus

public static final IntIntFunction plus

Function that returns a + b.

pow

public static final IntIntFunction pow

Function that returns (int) Math.pow(a,b).

shiftLeft

public static final IntIntFunction shiftLeft

Function that returns a << b.

shiftRightSigned

public static final IntIntFunction shiftRightSigned

Function that returns a >> b.

shiftRightUnsigned

public static final IntIntFunction shiftRightUnsigned

Function that returns a >>> b.

xor

public static final IntIntFunction xor

Function that returns a ^ b.

Method Detail

and

public static IntFunction and(int b)

Constructs a function that returns a & b. a is a variable, b is fixed.

between

public static IntFunction between(int from,
                                  int to)

Constructs a function that returns (from<=a && a<=to) ? 1 : 0. a is a variable, from and to are fixed.

bindArg1

public static IntFunction bindArg1(IntIntFunction function,
                                   int c)

Constructs a unary function from a binary function with the first operand (argument) fixed to the given constant c. The second operand is variable (free).

Parameters:

function - a binary function taking operands in the form function.apply(c,var).

Returns:

the unary function function(c,var).

bindArg2

public static IntFunction bindArg2(IntIntFunction function,
                                   int c)

Constructs a unary function from a binary function with the second operand (argument) fixed to the given constant c. The first operand is variable (free).

Parameters:

function - a binary function taking operands in the form function.apply(var,c).

Returns:

the unary function function(var,c).

chain

public static IntFunction chain(IntFunction g,
                                IntFunction h)

Constructs the function g( h(a) ).

Parameters:

g - a unary function.

h - a unary function.

Returns:

the unary function g( h(a) ).

chain

public static IntIntFunction chain(IntFunction g,
                                   IntIntFunction h)

Constructs the function g( h(a,b) ).

Parameters:

g - a unary function.

h - a binary function.

Returns:

the unary function g( h(a,b) ).

chain

public static IntIntFunction chain(IntIntFunction f,
                                   IntFunction g,
                                   IntFunction h)

Constructs the function f( g(a), h(b) ).

Parameters:

f - a binary function.

g - a unary function.

h - a unary function.

Returns:

the binary function f( g(a), h(b) ).

compare

public static IntFunction compare(int b)

Constructs a function that returns a < b ? -1 : a > b ? 1 : 0. a is a variable, b is fixed.

constant

public static IntFunction constant(int c)

Constructs a function that returns the constant c.

div

public static IntFunction div(int b)

Constructs a function that returns a / b. a is a variable, b is fixed.

equals

public static IntFunction equals(int b)

Constructs a function that returns a == b ? 1 : 0. a is a variable, b is fixed.

isBetween

public static IntProcedure isBetween(int from,
                                     int to)

Constructs a function that returns from<=a && a<=to. a is a variable, from and to are fixed.

isEqual

public static IntProcedure isEqual(int b)

Constructs a function that returns a == b. a is a variable, b is fixed.

isGreater

public static IntProcedure isGreater(int b)

Constructs a function that returns a > b. a is a variable, b is fixed.

isLess

public static IntProcedure isLess(int b)

Constructs a function that returns a < b. a is a variable, b is fixed.

max

public static IntFunction max(int b)

Constructs a function that returns Math.max(a,b). a is a variable, b is fixed.

min

public static IntFunction min(int b)

Constructs a function that returns Math.min(a,b). a is a variable, b is fixed.

minus

public static IntFunction minus(int b)

Constructs a function that returns a - b. a is a variable, b is fixed.

mod

public static IntFunction mod(int b)

Constructs a function that returns a % b. a is a variable, b is fixed.

mult

public static IntFunction mult(int b)

Constructs a function that returns a * b. a is a variable, b is fixed.

or

public static IntFunction or(int b)

Constructs a function that returns a | b. a is a variable, b is fixed.

plus

public static IntFunction plus(int b)

Constructs a function that returns a + b. a is a variable, b is fixed.

pow

public static IntFunction pow(int b)

Constructs a function that returns (int) Math.pow(a,b). a is a variable, b is fixed.

random

public static IntFunction random()

Constructs a function that returns a 32 bit uniformly distributed random number in the closed interval [Integer.MIN_VALUE,Integer.MAX_VALUE] (including Integer.MIN_VALUE and Integer.MAX_VALUE). Currently the engine is MersenneTwister and is seeded with the current time.

Note that any random engine derived from RandomEngine and any random distribution derived from AbstractDistribution are function objects, because they implement the proper interfaces. Thus, if you are not happy with the default, just pass your favourite random generator to function evaluating methods.

shiftLeft

public static IntFunction shiftLeft(int b)

Constructs a function that returns a << b. a is a variable, b is fixed.

shiftRightSigned

public static IntFunction shiftRightSigned(int b)

Constructs a function that returns a >> b. a is a variable, b is fixed.

shiftRightUnsigned

public static IntFunction shiftRightUnsigned(int b)

Constructs a function that returns a >>> b. a is a variable, b is fixed.

swapArgs

public static IntIntFunction swapArgs(IntIntFunction function)

Constructs a function that returns function.apply(b,a), i.e. applies the function with the first operand as second operand and the second operand as first operand.

Parameters:

function - a function taking operands in the form function.apply(a,b).

Returns:

the binary function function(b,a).

xor

public static IntFunction xor(int b)

Constructs a function that returns a | b. a is a variable, b is fixed.