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NAME

Math::AnyNum - Arbitrary size precision for integers, rationals, floating-points and complex numbers.

VERSION

Version 0.06

SYNOPSIS

Math::AnyNum provides a transparent and easy-to-use interface to Math::GMPq, Math::GMPz, Math::MPFR and Math::MPC.

    use 5.014;
    use Math::AnyNum qw(:overload factorial);

    # Integers
    say factorial(30);                            #=> 265252859812191058636308480000000

    # Floating-point numbers
    say sqrt(1 / factorial(100));                 #=> 1.0351378111756264713204945[...]e-79

    # Rational numbers
    my $x = 2/3;
    say ($x * 3);                                 #=> 2
    say (2 / $x);                                 #=> 3
    say $x;                                       #=> 2/3

    # Complex numbers
    say 3 + 4*i;                                  #=> 3+4i
    say sqrt(-4);                                 #=> 2i
    say log(-1);                                  #=> 3.1415926535897932384626433832[...]i

DESCRIPTION

Math::AnyNum focuses primarily on providing a friendly interface and good performance. In most cases, it can be used as a drop-in replacement for the bignum and bigrat pragmas.

The philosophy of Math::AnyNum is that mathematics should just work, therefore the support for complex number is virtually transparent, without requiring any explicit conversions. All the needed conversions are done implicitly, using a sophisticated promotion system, that tries really hard to do the right thing and as efficiently as possible.

In addition, each Math::AnyNum object is immutable.

HOW IT WORKS

Internally, each Math::AnyNum object holds a reference to an object of type Math::GMPz, Math::GMPq, Math::MPFR or Math::MPC. Based on the internal types, it decides what functions to call on each operation and does automatic promotion whenever necessarily.

The promotion rules can be summarized as follows:

    (Integer, Integer)   -> Integer | Rational | Float | Complex
    (Integer, Rational)  -> Rational | Float | Complex
    (Integer, Float)     -> Float | Complex
    (Integer, Complex)   -> Complex

    (Rational, Rational) -> Rational | Float | Complex
    (Rational, Float)    -> Float | Complex
    (Rational, Complex)  -> Complex

    (Float, Float)       -> Float | Complex
    (Float, Complex)     -> Complex

    (Complex, Complex)   -> Complex

For explicit conversion, Math::AnyNum provides the following methods:

    int(x)          # converts x to an integer (NaN if not possible)
    rat(x)          # converts x to a rational (NaN if not possible)
    float(x)        # converts x to a real-float (NaN if not possible)
    complex(x)      # converts x to a complex number (always possible)

IMPORT / EXPORT

The following functions are exportable:

    :trig
        sin sinh asin asinh
        cos cosh acos acosh
        tan tanh atan atanh
        cot coth acot acoth
        sec sech asec asech
        csc csch acsc acsch
        atan2 rad2deg deg2rad

    :special
        beta eta gamma lgamma lngamma digamma zeta
        Ai Ei Li Li2 LambertW BesselJ BesselY lgrt
        pow sqrt cbrt root exp ln log log2 log10 mod
        abs erf erfc sqr norm hypot agm bernreal harmreal

    :ntheory
        factorial dfactorial mfactorial primorial
        binomial lucas fibonacci bernfrac harmfrac
        lcm gcd valuation kronecker remdiv divmod
        iadd isub imul idiv imod ipow iroot isqrt
        icbrt ilog ilog2 ilog10 isqrtrem irootrem
        powmod invmod is_power is_square is_prime
        next_prime

    :misc
        rand irand seed iseed floor ceil round sgn neg inv
        conj int rat float complex real imag reals digits
        numerator denominator nude popcount as_bin as_hex
        as_oct as_int as_dec as_frac is_pos is_neg is_int
        is_rat is_real is_imag is_complex is_inf is_ninf
        is_nan is_zero is_one is_mone is_even is_odd is_div

Each function can be exported individually, as:

    use Math::AnyNum qw(zeta);

There is also the possibility of exporting an entire group of functions, as:

    use Math::AnyNum qw(:trig);

Additionally, by specifying the :all keyword, will export all the exportable functions and all the constants.

    use Math::AnyNum qw(:all);

The :overload keyword enables constant overloading, which makes each number a Math::AnyNum object and also exports the i, Inf and NaN constants:

    use Math::AnyNum qw(:overload);
    say 42;                                       #=> "42"   (as Int)
    say 1/2;                                      #=> "1/2"  (as Rat)
    say 0.5;                                      #=> "0.5"  (as Float)
    say 3 + 4*i;                                  #=> "3+4i" (as Complex)

NOTE: :overload is lexical to the current scope only.

The syntax for disabling the :overload behavior in the current scope, is:

    no Math::AnyNum;        # :overload will be disabled in the current scope

In addition to the exportable functions, Math::AnyNum also provides a list with useful mathematical constants that can be exported.

This constants are:

    i           # imaginary unit             sqrt(-1)
    e           # e mathematical constant    2.718281828459...
    pi          # PI constant                3.141592653589...
    tau         # TAU constant               6.283185307179...
    ln2         # natural logarithm of 2     0.693147180559...
    phi         # golden ratio               1.618033988749...
    euler       # Euler-Mascheroni constant  0.577215664901...
    catalan     # Catalan constant           0.915965594177...
    Inf         # positive Infinity
    NaN         # Not-a-Number

The syntax for importing a constant, is:

    use Math::AnyNum qw(pi);
    say pi;                          # 3.141592653589...

Nothing is exported by default.

PRECISION

The default precision for floating-point numbers is 192 bits, which is equivalent with about 50 digits of precision in base 10.

The precision can be changed by modifying the $Math::AnyNum::PREC variable, such as:

    local $Math::AnyNum::PREC = 1024;

or by specifying the precision at import (this sets the precision globally):

    use Math::AnyNum PREC => 1024;

This precision is used internally whenever a Math::MPFR or a Math::MPC object is created.

For example, if we change the precision to 3 decimal digits (where 4 is the conversion factor), we get the following results:

    local $Math::AnyNum::PREC = 3*4;
    say sqrt(2);                                  #=> 1.41
    say 98**7;                                    #=> 86812553324672
    say 1 / 98**7                                 #=> 1/86812553324672

As shown above, integers and rational numbers do not obey this precision, because they can grow and shrink dynamically, without a specific limit.

A rational number never losses accuracy in rational operations, therefore if we say:

    my $x = 1/3;
    say $x*3;                                     #=> 1
    say 1/$x;                                     #=> 3
    say 3/$x;                                     #=> 9

...the results are exact.

NOTATIONS

Methods that begin with an i followed by the actual name (e.g.: isqrt), do integer operations, by first truncating their arguments to integers, if necessary.

The returned types are noted as follows:

    Any         # any type of number
    Int         # an integer value
    Rat         # a rational value
    Float       # a floating-point value
    Complex     # a complex value
    NaN         # "Not-a-Number" value
    Inf         # +/-Infinity
    Bool        # a Boolean value (1 or 0)
    Scalar      # a Perl scalar

When two or more types are separated with pipe characters (|), it means that the corresponding function can return any of the specified types.

INITIALIZATION / CONSTANTS

This section includes methods for creating new Math::AnyNum objects and some useful mathematical constants.

new

    Math::AnyNum->new(n)                          #=> Any
    Math::AnyNum->new(n, base)                    #=> Any

Returns a new AnyNum object with the value specified in the first argument, which can be a Perl numerical value, a string representing a number in a rational form, such as "1/2", a string holding a floating-point number, such as "0.5", a string holding an integer, such as "255" or a string holding a complex number, such 3+4i.

    my $z = Math::AnyNum->new('42');        # integer
    my $r = Math::AnyNum->new('3/4');       # rational
    my $f = Math::AnyNum->new('12.34');     # float
    my $c = Math::AnyNum->new('3+4i');      # complex

The second argument specifies the base of the number, which can range from 2 to 36 inclusive and defaults to 10.

For setting an hexadecimal number, we can say:

    my $n = Math::AnyNum->new("deadbeef", 16);

NOTE: no prefix, such as "0x" or "0b", is allowed as part of the number.

new_si

    Math::AnyNum->new_si(n)                       #=> Int

Sets a signed native integer.

Example:

    my $n = Math::AnyNum->new_si(-42);

new_ui

    Math::AnyNum->new_ui(n)                       #=> Int

Sets an unsigned native integer.

Example:

    my $n = Math::AnyNum->new_ui(42);

new_z

    Math::AnyNum->new_z(str)                      #=> Int
    Math::AnyNum->new_z(str, base)                #=> Int

Sets an arbitrary large integer from a given string. When no base is specified, it defaults to base 10.

Example:

    my $n = Math::AnyNum->new_z("12345678910111213141516");
    my $m = Math::AnyNum->new_z("fffffffffffffffffff", 16);

new_q

    Math::AnyNum->new_q(frac)                     #=> Rat
    Math::AnyNum->new_q(num, den)                 #=> Rat
    Math::AnyNum->new_q(num, den, base)           #=> Rat

Sets an arbitrary large rational from a given string. When no base is specified, it defaults to base 10.

Example:

    my $n = Math::AnyNum->new_q('12345/67890');
    my $m = Math::AnyNum->new_q('12345', '67890');
    my $o = Math::AnyNum->new_q('fffff', 'aaaaa', 16);

new_f

    Math::AnyNum->new_f(str)                      #=> Float
    Math::AnyNum->new_f(str, base)                #=> Float

Sets a floating-point real number from a given string. When no base is specified, it defaults to base 10.

Example:

    my $n = Math::AnyNum->new_f('12.345');
    my $m = Math::AnyNum->new_f('-1.2345e-12');
    my $o = Math::AnyNum->new_f('ffffff', 16);

new_c

    Math::AnyNum->new_c(real)                     #=> Complex
    Math::AnyNum->new_c(real, imag)               #=> Complex
    Math::AnyNum->new_c(real, imag, base)         #=> Complex

Sets a complex number from a given string. When no base is specified, it defaults to base 10.

Example:

    my $n = Math::AnyNum->new_c('1.123');
    my $m = Math::AnyNum->new_c('3', '4');
    my $o = Math::AnyNum->new_c('f', 'a', 16);

nan

    Math::AnyNum->nan                             #=> NaN

Returns an object holding the NaN value.

inf

    Math::AnyNum->inf                             #=> Inf

Returns an object representing positive infinity.

ninf

    Math::AnyNum->ninf                            #=> -Inf

Returns an object representing negative infinity.

one

    Math::AnyNum->one                             #=> Int

Returns an object containing the value 1.

mone

    Math::AnyNum->mone                            #=> Int

Returns an object containing the value -1.

zero

    Math::AnyNum->zero                            #=> Int

Returns an object containing the value 0.

pi

    Math::AnyNum->pi                              #=> Float

Returns the number PI, which is 3.1415....

tau

    Math::AnyNum->tau                             #=> Float

Returns the number TAU, which is 2*pi.

ln2

    Math::AnyNum->ln2                             #=> Float

Returns the natural logarithm of 2.

euler

    Math::AnyNum->euler                           #=> Float

Returns the Euler-Mascheroni constant, which is 0.57721....

catalan

    Math::AnyNum->catalan                         #=> Float

Returns the value of Catalan's constant, also known as Beta(2) or G, and starts as: 0.91596....

i

    Math::AnyNum->i                               #=> Float

Returns the imaginary unit, which is sqrt(-1).

e

    Math::AnyNum->e                               #=> Float

Returns the e mathematical constant, which is 2.718....

phi

    Math::AnyNum->phi                             #=> Float

Returns the value of the golden ratio, which is 1.61803....

ARITHMETIC OPERATIONS

This section includes basic arithmetic operations.

add

    x + y                                         #=> Any

Adds x and y and returns the result.

sub

    x - y                                         #=> Any

Subtracts y from x and returns the result.

mul

    x * y                                         #=> Any

Multiplies x by y and returns the result.

div

    x / y                                         #=> Any

Divides x by y and returns the result.

mod

    x % y                                         #=> Any
    mod(x, y)                                     #=> Any

Remainder of x when is divided by y. Returns NaN when y is zero.

Implemented as:

    x % y = x - y*floor(x/y)

conj

    conj(x)                                       #=> Any

Complex conjugate of x. Return x when x is a real number.

Example:

    conj("3+4i") = 3-4*i

inv

    inv(x)                                        #=> Any

Multiplicative inverse of x. Equivalent with 1/x.

neg

    neg(x)                                        #=> Any

Additive inverse of x. Equivalent with -x.

abs

    abs(x)                                        #=> Float | Inf | NaN

Absolute value of x.

sqr

    sqr(x)                                        #=> Any

Multiplies x with itself and returns the result. Equivalent with x*x.

norm

    norm(x)                                       #=> Any

The square of the absolute value of x. Equivalent with abs(x)**2.

SPECIAL FUNCTIONS

This section includes the special functions.

sqrt

    sqrt(x)                                       #=> Any

Square root of x. Returns a complex number when x is negative.

cbrt

    cbrt(x)                                       #=> Any

Cube root of x. Returns a complex number x is negative.

root

    root(x, y)                                    #=> Any

The y root of x. Equivalent with x**(1/y).

pow

    x ** y                                        #=> Any
    pos(x, y)                                     #=> Any

Raises x to power y and returns the result.

When both x and y are integers, it does integer exponentiation and returns the exact result.

When only y is an integer, it does rational exponentiation based on the identity: (a/b)**n = a**n / b**n, which also computes the exact result.

Otherwise, it does floating-point exponentiation, which is equivalent with exp(log(x) * y).

exp

    exp(x)                                        #=> Any

Natural exponentiation of x (i.e.: e**x).

ln / log

    ln(x)                                         #=> Any
    log(x)                                        #=> Any
    log(x, y)                                     #=> Any

Logarithm of x to base y (or base e when y is omitted).

NOTE: log(x, y) is equivalent with log(x) / log(y).

log2 / log10

    log2(x)                                       #=> Any
    log10(x)                                      #=> Any

Logarithm of x to base 2 or base 10, respectively.

lgrt

    lgrt(x)                                       #=> Any

Logarithmic-root of x, which is the largest solution to a**a = b, where b is known. When the value of x is less than e**(-1/e), it returns a complex number. It also accepts complex numbers as input.

Example:

     lgrt(100)            # solves for x in `x**x = 100` and returns: `3.59728...`

LambertW

    LambertW(x)                                   #=> Any

The Lambert-W function. When the value of x is less than -1/e, it returns a complex number. It also accepts complex numbers as input.

Example:

     exp(LambertW(log(100)))    # solves for x in `x**x = 100` and returns: `3.59728...`

bernfrac

    bernfrac(n)                                   #=> Rat | NaN

Returns the nth-Bernoulli number B_n as an exact fraction, computed with an optimized version of Seidel's algorithm, starting with bernfrac(0) = 1.

For n >= 50, a more efficient algorithm is used, based on zeta(n).

Returns NaN for negatives values of n.

bernreal

    bernreal(n)                                   #=> Float | NaN

Returns the nth-Bernoulli number, as a floating-point approximation, with bernreal(0) = 1.

Returns NaN for negatives values of n.

harmfrac

    harmfrac(n)                                   #=> Rat | NaN

Returns the nth-Harmonic number H_n. The harmonic numbers are the sum of reciprocals of the first n natural numbers: 1 + 1/2 + 1/3 + ... + 1/n.

For values greater than 7000, binary splitting (Fredrik Johansson's elegant formulation) is used.

harmreal

    harmreal(n)                                   #=> Float | NaN

Returns the nth-Harmonic number, as a floating-point approximation, for any real value of n.

Returns NaN for negative integers.

Defined as:

    harmreal(n) = digamma(n+1) + euler

where euler is the Euler-Mascheroni constant.

agm

    agm(x, y)                                     #=> Any

Arithmetic-geometric mean of x and y.

Also defined for complex numbers.

hypot

    hypot(x, y)                                   #=> Any

The value of the hypotenuse for catheti x and y. Equivalent to sqrt(x**2 + y**2).

Also defined for complex numbers.

gamma

    gamma(x)                                      #=> Float | Inf | NaN

The Gamma function on x. Returns Inf when x is zero, and NaN when x is a negative integer.

lgamma

    lgamma(x)                                     #=> Float | Inf | NaN

The logarithm of the absolute value of the Gamma function. Returns Inf when x is negative or equal to zero.

lngamma

    lngamma(x)                                    #=> Float | Inf

The natural logarithm of the Gamma function on x. Returns Inf when x is negative or equal to zero.

digamma

    digamma(x)                                    #=> Float | Inf | NaN

The Digamma function (sometimes called Psi). Returns Nan when x is negative, and -Inf when x is 0.

beta

    beta(x, y)                                    #=> Float | Inf | NaN

The beta function (also called the Euler integral of the first kind).

Defined as:

    beta(x, y) = gamma(x)*gamma(y) / gamma(x+y)

zeta

    zeta(x)                                       #=> Float | Inf | NaN

The Riemann zeta function at x. Returns Inf when x is 1.

eta

    eta(x)                                        #=> Float | Inf | NaN

The Dirichlet eta function at x.

Defined as:

    eta(1) = ln(2)
    eta(x) = (1 - 2**(1-x)) * zeta(x)

BesselJ

    BesselJ(x, n)                                 #=> Float | NaN

The first order Bessel function, J_n(x), where n is a signed integer.

Example:

    BesselJ(x, n)        # represents J_n(x)

BesselY

    BesselY(x, n)                                 #=> Float | NaN

The second order Bessel function, Y_n(x), where n is a signed integer. Returns NaN for negative values of x.

Example:

    BesselY(x, n)        # represents Y_n(x)

erf

    erf(x)                                        #=> Float

The error function on x.

erfc

    erfc(x)                                       #=> Float

Complementary error function on x.

Ai

    Ai(x)                                         #=> Float

The Airy function on x.

Ei

    Ei(x)                                         #=> Float | Inf | NaN

Exponential integral of x. Returns -Inf when x is zero, and NaN when x is negative.

Li

    Li(x)                                         #=> Float | Inf | NaN

The logarithmic integral of x, defined as: Ei(ln(x)). Returns -Inf when x is 1, and Nan when x is less than or equal to 0.

Li2

    Li2(x)                                        #=> Float

The dilogarithm function, defined as the integral of -log(1-t)/t from 0 to x.

TRIGONOMETRIC FUNCTIONS

sin / sinh / asin / asinh

    sin(x)                                        #=> Any
    sinh(x)                                       #=> Any
    asin(x)                                       #=> Any
    asinh(x)                                      #=> Any

Sine, hyperbolic sine, inverse sine and inverse hyperbolic sine.

cos / cosh / acos / acosh

    cos(x)                                        #=> Any
    cosh(x)                                       #=> Any
    acos(x)                                       #=> Any
    acosh(x)                                      #=> Any

Cosine, hyperbolic cosine, inverse cosine and inverse hyperbolic cosine.

tan / tanh / atan / atanh

    tan(x)                                        #=> Any
    tanh(x)                                       #=> Any
    atan(x)                                       #=> Any
    atanh(x)                                      #=> Any

Tangent, hyperbolic tangent, inverse tangent and inverse hyperbolic tangent.

cot / coth / acot / acoth

    cot(x)                                        #=> Any
    coth(x)                                       #=> Any
    acot(x)                                       #=> Any
    acoth(x)                                      #=> Any

Cotangent, hyperbolic cotangent, inverse cotangent and inverse hyperbolic cotangent.

sec / sech / asec / asech

    sec(x)                                        #=> Any
    sech(x)                                       #=> Any
    asec(x)                                       #=> Any
    asech(x)                                      #=> Any

Secant, hyperbolic secant, inverse secant and inverse hyperbolic secant.

csc / csch / acsc / acsch

    csc(x)                                        #=> Any
    csch(x)                                       #=> Any
    acsc(x)                                       #=> Any
    acsch(x)                                      #=> Any

Cosecant, hyperbolic cosecant, inverse cosecant and inverse hyperbolic cosecant.

atan2

    atan2(x, y)                                   #=> Any

The arctangent of the quotient of its arguments (i.e.: atan(x/y)).

deg2rad

    deg2rad(x)                                    #=> Any

Returns the value of x converted from degrees to radians.

Example:

    deg2rad(180) = pi

rad2deg

    rad2deg(x)                                    #=> Any

Returns the value of x converted from radians to degrees.

Example:

    rad2deg(pi) = 180

INTEGER FUNCTIONS

All operations in this section are done with integers.

iadd / isub / imul / idiv / ipow

Integer addition, subtraction, multiplication, division and exponentiation.

imod

    imod(x, y)                                    #=> Int | NaN

The integer modulus operation. Returns NaN when y is zero.

divmod

    divmod(x, y)                                  #=> (Int, Int) | (NaN, NaN)

Returns the quotient and the remainder from division of x by y, where both are integers. When y is zero, it returns two NaN values.

invmod

    invmod(x, y)

Computes the inverse of x modulo y and returns the result. When no inverse exists, the NaN value is returned.

powmod

    powmod(x, y, z)                               #=> Int | NaN

Calculates (x ** y) % z, where all three values are integers.

Returns NaN when the third argument is 0.

isqrt / icbrt

    isqrt(n)                                      #=> Int | NaN
    icbrt(n)                                      #=> Int | NaN

The integer square root of n and the integer cube root of n. Returns NaN when a real root does not exists.

isqrtrem

    isqrtrem(n)                                   #=> (Int, Int) | (NaN, NaN)

The integer part of the square root of n and the remainder n - isqrt(n)**2, which will be zero when <n> is a perfect square.

iroot

    iroot(n, m)                                   #=> Int | NaN

The integer m-th root of n. Returns NaN when the root is not real.

irootrem

    irootrem(n, m)                                #=> (Int, Int) | (NaN, NaN)

The integer part of the root of n and the remainder n - iroot(n,m)**m.

Returns (NaN,NaN) when n is negative.

ilog

    ilog(n)                                       #=> Int | NaN
    ilog(n, m)                                    #=> Int | NaN

The integer part of the logarithm of n to base m or base e when m is not specified.

Return NaN when n is negative.

ilog2 / ilog10

    ilog2(n)                                      #=> Int | NaN
    ilog10(n)                                     #=> Int | NaN

The integer part of the logarithm of n to base 2 or base 10, respectively.

and / or / xor / not / lsft / rsft

    x & y                                         #=> Int
    x | y                                         #=> Int
    x ^ y                                         #=> Int
    ~x                                            #=> Int
    x << y                                        #=> Int
    x >> y                                        #=> Int

The integer-logical operations.

gcd

    gcd(x, y)                                     #=> Int

The greatest common divisor of x and y.

lcm

    lcm(x, y)                                     #=> Int

The least common multiple of x and y.

valuation

    valuation(n, k)                               #=> Scalar

Returns the number of times n is divisible by k.

remdiv

    remdiv(n, k)                                  #=> Int

Removes all occurrences of the factor k from integer n.

In general, the following statement holds true:

    remdiv(n, k) == n / k**valuation(n, k)

kronecker

    kronecker(n, m)                               #=> Scalar

Returns the Kronecker symbol (n|m), which is a generalization of the Jacobi symbol for all integers m.

lucas

    lucas(n)                                      #=> Int | NaN

The n-th Lucas number. Returns NaN when n is negative.

fibonacci

    fibonacci(n)                                  #=> Int | NaN

The n-th Fibonacci number. Returns NaN when n is negative.

factorial

    factorial(n)                                  #=> Int | NaN

Factorial of n. Returns NaN when n is negative. (1*2*3*...*n)

dfactorial

    dfactorial(n)                                 #=> Int | NaN

Double-factorial of n (denoted as n!!). Returns NaN when n is negative. (requires GMP>=5.1.0)

Example:

    dfactorial(7)     # 1*3*5*7 = 105
    dfactorial(8)     # 2*4*6*8 = 384

mfactorial

    mfactorial(n, m)                              #=> Int | NaN

Generalized m-factorial of n. Returns NaN when n is negative. (requires GMP>=5.1.0)

binomial

    binomial(n, k)                                #=> Int

Calculates the binomial coefficient n over k, also called the "choose" function. The result is equivalent to:

           ( n )       n!
           |   |  = -------
           ( k )    k!(n-k)!

primorial

    primorial(n)                                  #=> Int

Returns the product of all the primes less than or equal to n. (requires GMP>=5.1.0)

next_prime

    next_prime(n)                                 #=> Int

Returns the next prime after n.

is_prime

    is_prime(n)                                   #=> Scalar
    is_prime(n, r)                                #=> Scalar

Returns 2 if n is definitely prime, 1 if n is probably prime (without being certain), or 0 if n is definitely composite. This method does some trial divisions, then some Miller-Rabin probabilistic primality tests. It also accepts an optional argument for specifying the accuracy of the test. By default, it uses an accuracy value of 20.

Reasonable accuracy values are between 15 and 50.

See also:

is_power

    is_power(n)
    is_power(n, k)                                #=> Bool

Return a true value when n is a perfect power of a given integer k.

When n is not an integer, it always returns false. On the other hand, when k is not an integer, it will implicitly be truncated to an integer. If k is not positive after truncation, 0 is returned.

A true value is returned iff there exists some integer a satisfying the equation: a**k = n.

When k is not specified, it returns true if n can be expressed as a**b for some integers a and b.

Example:

    is_power(100, 2)       # true: 100 is a square (10**2)
    is_power(125, 3)       # true: 125 is a cube   ( 5**3)
    is_power(279841)       # true: 279841 is 23**4

is_square

    is_square(n)                                  #=> Bool

Returns a true value when n is a perfect square. When n is not an integer, a false value is returned.

MISCELLANEOUS

This section includes various useful methods.

floor

    floor(x)                                      #=> Any

Returns x if x is an integer, otherwise it rounds x towards -Infinity.

Example:

    floor( 2.5) =  2
    floor(-2.5) = -3

ceil

    ceil(x)                                       #=> Any

Returns x if x is an integer, otherwise it rounds x towards +Infinity.

Example:

    ceil( 2.5) =  3
    ceil(-2.5) = -2

round

    round(x)                                      #=> Any
    round(x, p)                                   #=> Any

Rounds x to the nth place. A negative argument rounds that many digits after the decimal point, while a positive argument rounds that many digits before the decimal point.

Example:

    round('1234.567')         = 1235
    round('1234.567', 2)      = 1200
    round('3.123+4.567i', -2) = 3.12+4.57*i

rand

    rand(x)                                       #=> Float
    rand(x, y)                                    #=> Float

Returns a pseudorandom floating-point value. When an additional argument is provided, it returns a number between x (inclusive) and y (exclusive). Otherwise, returns a number between 0 (inclusive) and x (exclusive).

The PRNG behind this function is called the "Mersenne Twister". Although it generates pseudorandom numbers of very good quality, it is NOT cryptographically secure!

Example:

    rand(10)        # a random number in the range [0, 10)
    rand(10, 20)    # a random number in the range [10, 20)

irand

    irand(x)                                      #=> Int
    irand(x, y)                                   #=> Int

Returns a pseudorandom integer. Unlike the rand() function, irand() is inclusive in both sides.

When an additional argument is provided, it returns an integer between x (inclusive) and y (inclusive), otherwise returns an integer between 0 (inclusive) and x (inclusive).

If x is greater that y, the returned result will be in the range [y, x].

The PRNG behind this method is called the "Mersenne Twister". Although it generates high-quality pseudorandom integers, it is NOT cryptographically secure!

Example:

    irand(10)        # a random integer in the range [0, 10]
    irand(10, 20)    # a random integer in the range [10, 20]

seed / iseed

    seed(n)                                       #=> Int
    iseed(n)                                      #=> Int

Reseeds the rand() and the irand() function, respectively, with the value of n, which can be any arbitrary large integer.

Returns back the integer part of n. If n cannot be truncated to an integer, the method dies with an appropriate error message.

sgn

    sgn(x)                                        #=> Scalar | Complex

Returns -1 when x is negative, 1 when x is positive, and 0 when x is zero.

When x is a complex number, it computes the sign using the identity:

    sgn(x) = x / abs(x)

length

    length(x)                                     #=> Scalar

Returns the number digits in the integer part of x. Returns -1 when x cannot be converted to an integer.

For -1234.56, it returns 4.

inc

    ++$x                                          #=> Any
    $x++                                          #=> Any

Returns x + 1.

dec

    --$x                                          #=> Any
    $x--                                          #=> Any

Return x - 1.

copy

    $x->copy                                      #=> Any

Returns a deep-copy of the self-object.

popcount

    popcount(n)                                   #=> Scalar

Returns the population count of the positive integer part of x, which is the number of 1 bits in its binary representation.

This value is also known as the Hamming weight.

* Introspection

is_int

    is_int(x)                                     #=> Bool

Returns a true value when x is an integer.

is_rat

    is_rat(x)                                     #=> Bool

Returns a true value when x is a rational number.

is_real

    is_real(x)                                    #=> Bool

Returns a true value when x is a real number (i.e.: when the imaginary part is zero and it holds a real value in the real part).

Example:

    is_real(complex('4'))           # true
    is_real(complex('4i'))          # false (is imaginary)
    is_real(complex('3+4i'))        # false (is complex)

is_imag

Returns a true value when x is an imaginary number (i.e.: when the real part is zero and it has a non-zero imaginary part).

Example:

    is_imag(complex('4'))           # false (is real)
    is_imag(complex('4i'))          # true
    is_imag(complex('3+4i'))        # false (is complex)

is_complex

    is_complex(x)                                 #=> Bool

Returns a true value when x is a complex number (i.e.: when the real part and the imaginary part are non-zero).

Example:

    is_complex(complex('4'))        # false (is real)
    is_complex(complex('4i'))       # false (is imaginary)
    is_complex(complex('3+4i'))     # true

is_even

    is_even(n)                                    #=> Bool

Returns a true value when n is a real integer divisible by 2.

is_odd

    is_odd(n)                                     #=> Bool

Returns a true value when n is a real integer not divisible by 2.

is_div

    is_div(x, y)                                  #=> Bool

Returns a true value when x is exactly divisible by y (i.e.: when the remainder x % y is zero).

This is a generalized version of the above two methods and it also works with complex numbers.

is_pos

    is_pos(x)                                     #=> Bool

Returns a true value when x is positive.

is_neg

    is_neg(x)                                     #=> Bool

Returns a true value when x is negative.

is_zero

    is_zero(n)                                    #=> Bool

Returns a true value when n equals 0.

is_one

    is_one(n)                                     #=> Bool

Returns a true value when n equals 1.

is_mone

    is_mone(n)                                    #=> Bool

Returns a true value when n equals -1.

is_inf

    is_inf(x)                                     #=> Bool

Returns a true value when x holds the positive Infinity special value.

is_ninf

    is_ninf(x)                                    #=> Bool

Returns a true value when x holds the negative Infinity special value.

is_nan

    is_nan(x)                                     #=> Bool

Returns a true value when x holds the Not-a-Number special value.

* Conversions

int

    int(x)                                        #=> Int | NaN

Returns the integer part of x. Returns NaN when it's not possible to truncate the number to an integer.

rat

    rat(x)                                        #=> Rat | NaN
    rat(str)                                      #=> Rat | NaN

Convert x to a rational number. Returns NaN when this conversion is not possible.

Example:

    rat('0.5')       = 1/2
    rat('1234/5678') = 617/2839

float

    float(x)                                      #=> Float | NaN
    float(str)                                    #=> Float | NaN

Converts x to a floating-point real number.

Example:

    float('3.14159') = 3.14159
    float('777/222') = 3.5

complex

    complex(x)                                    #=> Complex
    complex(str)                                  #=> Complex

Converts x to a complex number.

Example:

    complex("3+4i") = 3+4*i

stringify

    "$x"                                          #=> Scalar

Returns a string representing the value of x, either as a base-10 integer, or a decimal expansion.

boolify

    !!$x                                          #=> Bool

Returns a false value when the number is zero. True otherwise.

numify

    $x->numify                                    #=> Scalar

Returns a Perl numerical scalar containing the value of x, truncated if needed.

as_bin

    as_bin(n)                                     #=> Scalar

Returns a string representing the integer part of n in binary (base 2).

Example:

    as_bin(42) = "101010"

as_oct

    as_oct(n)                                     #=> Scalar

Returns a string representing the integer part of n in octal (base 8).

Example:

    as_oct(42) = "52"

as_hex

    as_hex(n)                                     #=> Scalar

Returns a string representing the value of n in hexadecimal (base 16).

Example:

    as_hex(42) = "2a"

as_int

    as_int(n)                                     #=> Scalar
    as_int(n, b)                                  #=> Scalar

Returns the integer part of n in a given base as a string. When the base is omitted, it defaults to base 10.

Example:

    as_int(255)     = "255"
    as_int(255, 16) = "ff"

as_frac

    as_frac(n)                                    #=> Scalar
    as_frac(n, b)                                 #=> Scalar

Returns a string representing n as a fraction in a given base. When the base is omitted, it defaults to base 10.

Example:

    as_frac(42)      = "42/1"
    as_frac("1/2")   = "1/2"
    as_frac(255, 16) = "ff/1"

as_dec

    as_dec(n)                                     #=> Scalar
    as_dec(n, digits)                             #=> Scalar

Returns a decimal expansion of the number n, as a string, with an optional number of digits. When the second argument is undefined, it uses the default precision.

Number n can also be a complex number.

Example:

    as_dec(1/2)        = "0.5"
    as_dec(sqrt(2), 3) = "1.41"

* Dissections

numerator

    numerator(x)                                  #=> Int | NaN

Returns the numerator as a signed Math::AnyNum object. When x is not a rational number, it tries to convert it to a rational. Returns NaN when this is not possible.

Example:

    numerator("-42")  = -42
    numerator("-3/4") = -3

denominator

    denominator(x)                                #=> Int | NaN

Returns the numerator as an unsigned Math::AnyNum object. When x is not a rational number, it tries to convert it to a rational. Returns NaN when this is not possible.

Example:

    denominator("-42")  = 1
    denominator("-3/4") = 4

nude

    nude(x)                                       #=> (Int | NaN, Int | NaN)

Returns the numerator and the denominator of x.

Example:

    nude("42")   = (42, 1)
    nude("-3/4") = (-3, 4)

real

    real(x)                                       #=> Any

Returns the real part of x.

Example:

    real("42")   = 42
    real("42i")  = 0
    real("3-4i") = 3

imag

    imag(x)                                       #=> Any

Returns the imaginary part of x, if any. Otherwise, returns zero.

Example:

    imag("42")   =  0
    imag("42i")  = 42
    imag("3-4i") = -4

reals

    reals(x)                                      #=> (Any, Any)

Return the real and the imaginary part of x as real numbers.

Example:

    reals("42")   = (42, 0)
    reals("42i")  = (0, 42)
    reals("3-4i") = (3, -4)

digits

    digits(x)                                     #=> (Scalar, Scalar, ...)
    digits(x, b)                                  #=> (Scalar, Scalar, ...)

Returns a list with the digits of x in a given base. When no base is specified, it defaults to base 10.

Only the absolute integer part of x is considered.

Example:

    digits(-1234.56) = (1,2,3,4)
    digits(4095, 16) = ('f','f','f')

* Comparisons

eq

    x == y                                        #=> Bool

Equality check: returns a true value when x and y are equal.

ne

    x != y                                        #=> Bool

Inequality check: returns a true value when x and y are not equal.

gt

    x > y                                         #=> Bool

Returns a true value when x is greater than y.

ge

    x >= y                                        #=> Bool

Returns a true value when x is equal or greater than y.

lt

    x < y                                         #=> Bool

Returns a true value when x is less than y.

le

    x <= y                                        #=> Bool

Returns a true value when x is equal or less than y.

cmp

    x <=> y                                       #=> Scalar

Compares x to y and returns a negative value when x is less than y, 0 when x and y are equal, and a positive value when x is greater than y.

Complex numbers are compared as:

    (real(x) <=> real(y)) ||
    (imag(x) <=> imag(y))

Comparing anything to NaN (including NaN itself), returns undef.

PERFORMANCE

The performance varies greatly, but, in most cases, Math::AnyNum is between 2x up to 10x faster than Math::BigFloat with the GMP backend, and about 100x faster than Math::BigFloat without the GMP backend (to be modest).

Math::AnyNum is fast because of the following facts:

  • minimal overhead in object creations and conversions.

  • minimal Perl code is executed per operation.

  • the GMP, MPFR and MPC libraries are extremely efficient.

To achieve the best performance, try to follow this rules:

  • use the i* functions/methods wherever applicable.

  • use floating-point numbers when accuracy is not important.

  • pass Perl numbers as arguments to methods, if you can.

MOTIVATION

This module came into existence as a response to Dana Jacobsen's request for a transparent interface to Math::GMPz and Math::MPFR, which he talked about at the YAPC NA, in 2015.

See his great presentation at: https://www.youtube.com/watch?v=Dhl4_Chvm_g.

The main aim of this module is to provide a fast and correct alternative to Math::BigInt, Maht::BigFloat and Math::BigRat, as well as to bigint, bignum and bigrat pragmas.

The original project was called Math::BigNum, but because of some design flaws, it was very hard to add support for complex numbers, therefore the project was abandoned and much of its code ended up in this module.

AUTHOR

Daniel Șuteu, <trizenx at gmail.com>

BUGS

Please report any bugs or feature requests to https://github.com/trizen/Math-AnyNum/issues. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc Math::AnyNum

You can also look for information at:

SEE ALSO

  • Fast math libraries

    Math::GMP - High speed arbitrary size integer math.

    Math::GMPz - perl interface to the GMP library's integer (mpz) functions.

    Math::GMPq - perl interface to the GMP library's rational (mpq) functions.

    Math::MPFR - perl interface to the MPFR (floating point) library.

    Math::MPC - perl interface to the MPC (multi precision complex) library.

  • Portable math libraries

    Math::BigInt - Arbitrary size integer/float math package.

    Math::BigFloat - Arbitrary size floating point math package.

    Math::BigRat - Arbitrary big rational numbers.

  • Math utilities

    Math::Prime::Util - Utilities related to prime numbers, including fast sieves and factoring.

LICENSE AND COPYRIGHT

Copyright 2017 Daniel Șuteu.

This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

Any use, modification, and distribution of the Standard or Modified Versions is governed by this Artistic License. By using, modifying or distributing the Package, you accept this license. Do not use, modify, or distribute the Package, if you do not accept this license.

If your Modified Version has been derived from a Modified Version made by someone other than you, you are nevertheless required to ensure that your Modified Version complies with the requirements of this license.

This license does not grant you the right to use any trademark, service mark, tradename, or logo of the Copyright Holder.

This license includes the non-exclusive, worldwide, free-of-charge patent license to make, have made, use, offer to sell, sell, import and otherwise transfer the Package with respect to any patent claims licensable by the Copyright Holder that are necessarily infringed by the Package. If you institute patent litigation (including a cross-claim or counterclaim) against any party alleging that the Package constitutes direct or contributory patent infringement, then this Artistic License to you shall terminate on the date that such litigation is filed.

Disclaimer of Warranty: THE PACKAGE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS IS' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES. THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED TO THE EXTENT PERMITTED BY YOUR LOCAL LAW. UNLESS REQUIRED BY LAW, NO COPYRIGHT HOLDER OR CONTRIBUTOR WILL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING IN ANY WAY OUT OF THE USE OF THE PACKAGE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.