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class Bignum
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Parent:
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Integer
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Version:
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1.6
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Index:
Arithmetic operations
Bit operations
<=>
[ ]
size
to_f
to_i
to_s
Bignum objects hold integers outside the range of
Fixnum.
Bignum objects are created automatically when
integer calculations would otherwise overflow a
Fixnum. When a
calculation involving
Bignum objects returns a result that will
fit in a
Fixnum, the result is automatically converted.
For the purposes of the bitwise operations and
[], a
Bignum is treated as if it were an infinite-length bitstring
with 2's complement representation.
While
Fixnum values are immediate,
Bignum objects are
not---assignment and parameter passing work with references to
objects, not the objects themselves.
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instance methods
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Arithmetic operations
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Performs various arithmetic operations on big.
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big
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+ |
aNumeric
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Addition |
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big
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-- |
aNumeric
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Subtraction |
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big
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* |
aNumeric
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Multiplication |
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big
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/ |
aNumeric
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Division |
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big
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% |
aNumeric
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Modulo |
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big
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** |
aNumeric
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Exponentiation |
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Bit operations
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Performs various operations on the binary
representations of the Bignum.
| ~ big
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Invert bits |
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big
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aNumeric
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Bitwise OR
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big
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& |
aNumeric
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Bitwise AND
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big
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^ |
aNumeric
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Bitwise EXCLUSIVE OR
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big
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<< |
aNumeric
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Left-shift aNumeric bits |
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big
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>> |
aNumeric
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Right-shift aNumeric bits
(with sign extension) |
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<=>
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big <=> aNumeric -> -1, 0, +1
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Comparison---Returns -1, 0, or +1 depending on
whether big is less
than, equal to, or greater than aNumeric. This is the
basis for the tests in Comparable.
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[ ]
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big[ n ] -> 0, 1
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Bit Reference---Returns the nth bit in
the (assumed) binary representation of big,
where big[0] is the least significant bit.
a = 9**15
50.downto(0) do |n|
print a[n]
end
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produces:
000101110110100000111000011110010100111100010111001
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size
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big.size -> anInteger
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Returns the number of bytes in the machine representation
of big.
(256**10 - 1).size
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� |
12
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(256**20 - 1).size
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� |
20
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(256**40 - 1).size
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� |
40
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to_f
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big.to_f -> aFloat
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Converts big to a Float. If big doesn't fit in a
Float, the result is infinity.
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to_i
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big.to_i ->
big
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Returns big.
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to_s
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big.to_s -> aString
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Returns a string containing the decimal representation of big.
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