內容

scale

use Math::BigFloat;

# Configuration methods (may be used as class methods and instance methods)

Math::BigFloat->accuracy();     # get class accuracy
Math::BigFloat->accuracy($n);   # set class accuracy
Math::BigFloat->precision();    # get class precision
Math::BigFloat->precision($n);  # set class precision
Math::BigFloat->round_mode();   # get class rounding mode
Math::BigFloat->round_mode($m); # set global round mode, must be one of
                                # 'even', 'odd', '+inf', '-inf', 'zero',
                                # 'trunc', or 'common'
Math::BigFloat->config("lib");  # name of backend math library

# Constructor methods (when the class methods below are used as instance
# methods, the value is assigned the invocand)

$x = Math::BigFloat->new($str);               # defaults to 0
$x = Math::BigFloat->new('0x123');            # from hexadecimal
$x = Math::BigFloat->new('0o377');            # from octal
$x = Math::BigFloat->new('0b101');            # from binary
$x = Math::BigFloat->from_hex('0xc.afep+3');  # from hex
$x = Math::BigFloat->from_hex('cafe');        # ditto
$x = Math::BigFloat->from_oct('1.3267p-4');   # from octal
$x = Math::BigFloat->from_oct('01.3267p-4');  # ditto
$x = Math::BigFloat->from_oct('0o1.3267p-4'); # ditto
$x = Math::BigFloat->from_oct('0377');        # ditto
$x = Math::BigFloat->from_bin('0b1.1001p-4'); # from binary
$x = Math::BigFloat->from_bin('0101');        # ditto
$x = Math::BigFloat->from_ieee754($b, "binary64");  # from IEEE-754 bytes
$x = Math::BigFloat->bzero();                 # create a +0
$x = Math::BigFloat->bone();                  # create a +1
$x = Math::BigFloat->bone('-');               # create a -1
$x = Math::BigFloat->binf();                  # create a +inf
$x = Math::BigFloat->binf('-');               # create a -inf
$x = Math::BigFloat->bnan();                  # create a Not-A-Number
$x = Math::BigFloat->bpi();                   # returns pi

$y = $x->copy();        # make a copy (unlike $y = $x)
$y = $x->as_int();      # return as BigInt
$y = $x->as_float();    # return as a Math::BigFloat
$y = $x->as_rat();      # return as a Math::BigRat

# Boolean methods (these don't modify the invocand)

$x->is_zero();          # if $x is 0
$x->is_one();           # if $x is +1
$x->is_one("+");        # ditto
$x->is_one("-");        # if $x is -1
$x->is_inf();           # if $x is +inf or -inf
$x->is_inf("+");        # if $x is +inf
$x->is_inf("-");        # if $x is -inf
$x->is_nan();           # if $x is NaN

$x->is_positive();      # if $x > 0
$x->is_pos();           # ditto
$x->is_negative();      # if $x < 0
$x->is_neg();           # ditto

$x->is_odd();           # if $x is odd
$x->is_even();          # if $x is even
$x->is_int();           # if $x is an integer

# Comparison methods

$x->bcmp($y);           # compare numbers (undef, < 0, == 0, > 0)
$x->bacmp($y);          # compare absolutely (undef, < 0, == 0, > 0)
$x->beq($y);            # true if and only if $x == $y
$x->bne($y);            # true if and only if $x != $y
$x->blt($y);            # true if and only if $x < $y
$x->ble($y);            # true if and only if $x <= $y
$x->bgt($y);            # true if and only if $x > $y
$x->bge($y);            # true if and only if $x >= $y

# Arithmetic methods

$x->bneg();             # negation
$x->babs();             # absolute value
$x->bsgn();             # sign function (-1, 0, 1, or NaN)
$x->bnorm();            # normalize (no-op)
$x->binc();             # increment $x by 1
$x->bdec();             # decrement $x by 1
$x->badd($y);           # addition (add $y to $x)
$x->bsub($y);           # subtraction (subtract $y from $x)
$x->bmul($y);           # multiplication (multiply $x by $y)
$x->bmuladd($y,$z);     # $x = $x * $y + $z
$x->bdiv($y);           # division (floored), set $x to quotient
                        # return (quo,rem) or quo if scalar
$x->btdiv($y);          # division (truncated), set $x to quotient
                        # return (quo,rem) or quo if scalar
$x->bmod($y);           # modulus (x % y)
$x->btmod($y);          # modulus (truncated)
$x->bmodinv($mod);      # modular multiplicative inverse
$x->bmodpow($y,$mod);   # modular exponentiation (($x ** $y) % $mod)
$x->bpow($y);           # power of arguments (x ** y)
$x->blog();             # logarithm of $x to base e (Euler's number)
$x->blog($base);        # logarithm of $x to base $base (e.g., base 2)
$x->bexp();             # calculate e ** $x where e is Euler's number
$x->bnok($y);           # x over y (binomial coefficient n over k)
$x->bsin();             # sine
$x->bcos();             # cosine
$x->batan();            # inverse tangent
$x->batan2($y);         # two-argument inverse tangent
$x->bsqrt();            # calculate square root
$x->broot($y);          # $y'th root of $x (e.g. $y == 3 => cubic root)
$x->bfac();             # factorial of $x (1*2*3*4*..$x)

$x->blsft($n);          # left shift $n places in base 2
$x->blsft($n,$b);       # left shift $n places in base $b
                        # returns (quo,rem) or quo (scalar context)
$x->brsft($n);          # right shift $n places in base 2
$x->brsft($n,$b);       # right shift $n places in base $b
                        # returns (quo,rem) or quo (scalar context)

# Bitwise methods

$x->band($y);           # bitwise and
$x->bior($y);           # bitwise inclusive or
$x->bxor($y);           # bitwise exclusive or
$x->bnot();             # bitwise not (two's complement)

# Rounding methods
$x->round($A,$P,$mode); # round to accuracy or precision using
                        # rounding mode $mode
$x->bround($n);         # accuracy: preserve $n digits
$x->bfround($n);        # $n > 0: round to $nth digit left of dec. point
                        # $n < 0: round to $nth digit right of dec. point
$x->bfloor();           # round towards minus infinity
$x->bceil();            # round towards plus infinity
$x->bint();             # round towards zero

# Other mathematical methods

$x->bgcd($y);            # greatest common divisor
$x->blcm($y);            # least common multiple

# Object property methods (do not modify the invocand)

$x->sign();              # the sign, either +, - or NaN
$x->digit($n);           # the nth digit, counting from the right
$x->digit(-$n);          # the nth digit, counting from the left
$x->length();            # return number of digits in number
($xl,$f) = $x->length(); # length of number and length of fraction
                         # part, latter is always 0 digits long
                         # for Math::BigInt objects
$x->mantissa();          # return (signed) mantissa as BigInt
$x->exponent();          # return exponent as BigInt
$x->parts();             # return (mantissa,exponent) as BigInt
$x->sparts();            # mantissa and exponent (as integers)
$x->nparts();            # mantissa and exponent (normalised)
$x->eparts();            # mantissa and exponent (engineering notation)
$x->dparts();            # integer and fraction part
$x->fparts();            # numerator and denominator
$x->numerator();         # numerator
$x->denominator();       # denominator

# Conversion methods (do not modify the invocand)

$x->bstr();         # decimal notation, possibly zero padded
$x->bsstr();        # string in scientific notation with integers
$x->bnstr();        # string in normalized notation
$x->bestr();        # string in engineering notation
$x->bdstr();        # string in decimal notation
$x->bfstr();        # string in fractional notation

$x->as_hex();       # as signed hexadecimal string with prefixed 0x
$x->as_bin();       # as signed binary string with prefixed 0b
$x->as_oct();       # as signed octal string with prefixed 0
$x->to_ieee754($format); # to bytes encoded according to IEEE 754-2008

# Other conversion methods

$x->numify();           # return as scalar (might overflow or underflow)

內容

#名稱

#語法

#說明

#輸入

#輸出

#方法

#組態方法

#建構函式方法

#算術方法

#ACCURACY AND PRECISION

#捨入

#數值文字

#十六進位、八進位和二進位浮點文字

#數學函式庫

#使用 Math::BigInt::Lite

#匯出

#注意事項

#BUGS

#支援

#授權

#另請參閱

#作者