An Integer object represents an integer value.
You can create an Integer object explicitly with:
-
An integer literal.
You can convert certain objects to Integers with:
-
Method
Integer.
An attempt to add a singleton method to an instance of this class causes an exception to be raised.
What’s Here
First, what’s elsewhere. Class Integer:
-
Inherits from class Numeric.
Here, class Integer provides methods for:
Querying
-
allbits?: Returns whether all bits inselfare set. -
anybits?: Returns whether any bits inselfare set. -
nobits?: Returns whether no bits inselfare set.
Comparing
-
<: Returns whetherselfis less than the given value. -
<=: Returns whetherselfis less than or equal to the given value. -
<=>: Returns a number indicating whetherselfis less than, equal to, or greater than the given value. -
==(aliased as===): Returns whetherselfis equal to the givenvalue.
-
>: Returns whetherselfis greater than the given value. -
>=: Returns whetherselfis greater than or equal to the given value.
Converting
-
::sqrt: Returns the integer square root of the given value. -
::try_convert: Returns the given value converted to an Integer. -
&: Returns the bitwise AND ofselfand the given value. -
*: Returns the product ofselfand the given value. -
**: Returns the value ofselfraised to the power of the given value. -
+: Returns the sum ofselfand the given value. -
-: Returns the difference ofselfand the given value. -
/: Returns the quotient ofselfand the given value. -
<<: Returns the value ofselfafter a leftward bit-shift. -
>>: Returns the value ofselfafter a rightward bit-shift. -
[]: Returns a slice of bits fromself. -
^: Returns the bitwise EXCLUSIVE OR ofselfand the given value. -
ceil: Returns the smallest number greater than or equal toself. -
chr: Returns a 1-character string containing the character represented by the value ofself. -
digits: Returns an array of integers representing the base-radix digits ofself. -
div: Returns the integer result of dividingselfby the given value. -
divmod: Returns a 2-element array containing the quotient and remainder results of dividingselfby the given value. -
fdiv: Returns theFloatresult of dividingselfby the given value. -
floor: Returns the greatest number smaller than or equal toself. -
pow: Returns the modular exponentiation ofself. -
pred: Returns the integer predecessor ofself. -
remainder: Returns the remainder after dividingselfby the given value. -
round: Returnsselfrounded to the nearest value with the given precision. -
succ(aliased asnext): Returns the integer successor ofself. -
to_s(aliased asinspect): Returns a string containing the place-value representation ofselfin the given radix. -
truncate: Returnsselftruncated to the given precision. -
|: Returns the bitwise OR ofselfand the given value.
Other
The version of loaded GMP.
static VALUE
rb_int_s_isqrt(VALUE self, VALUE num)
{
unsigned long n, sq;
num = rb_to_int(num);
if (FIXNUM_P(num)) {
if (FIXNUM_NEGATIVE_P(num)) {
domain_error("isqrt");
}
n = FIX2ULONG(num);
sq = rb_ulong_isqrt(n);
return LONG2FIX(sq);
}
else {
size_t biglen;
if (RBIGNUM_NEGATIVE_P(num)) {
domain_error("isqrt");
}
biglen = BIGNUM_LEN(num);
if (biglen == 0) return INT2FIX(0);
#if SIZEOF_BDIGIT <= SIZEOF_LONG
/* short-circuit */
if (biglen == 1) {
n = BIGNUM_DIGITS(num)[0];
sq = rb_ulong_isqrt(n);
return ULONG2NUM(sq);
}
#endif
return rb_big_isqrt(num);
}
}
Returns the integer square root of the non-negative integer n, which is the largest non-negative integer less than or equal to the square root of numeric.
Integer.sqrt(0) # => 0 Integer.sqrt(1) # => 1 Integer.sqrt(24) # => 4 Integer.sqrt(25) # => 5 Integer.sqrt(10**400) # => 10**200
If numeric is not an Integer, it is converted to an Integer:
Integer.sqrt(Complex(4, 0)) # => 2 Integer.sqrt(Rational(4, 1)) # => 2 Integer.sqrt(4.0) # => 2 Integer.sqrt(3.14159) # => 1
This method is equivalent to Math.sqrt(numeric).floor, except that the result of the latter code may differ from the true value due to the limited precision of floating point arithmetic.
Integer.sqrt(10**46) # => 100000000000000000000000 Math.sqrt(10**46).floor # => 99999999999999991611392
Raises an exception if numeric is negative.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 320
def Integer.try_convert(num)
=begin
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_check_integer_type(num)'
=end
end
If object is an Integer object, returns object.
Integer.try_convert(1) # => 1
Otherwise if object responds to :to_int, calls object.to_int and returns the result.
Integer.try_convert(1.25) # => 1
Returns nil if object does not respond to :to_int
Integer.try_convert([]) # => nil
Raises an exception unless object.to_int returns an Integer object.
VALUE
rb_int_modulo(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_mod(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_modulo(x, y);
}
return num_modulo(x, y);
}
Returns self modulo other as a real number.
For integer n and real number r, these expressions are equivalent:
n % r n-r*(n/r).floor n.divmod(r)[1]
See Numeric#divmod.
Examples:
10 % 2 # => 0 10 % 3 # => 1 10 % 4 # => 2 10 % -2 # => 0 10 % -3 # => -2 10 % -4 # => -2 10 % 3.0 # => 1.0 10 % Rational(3, 1) # => (1/1)
Integer#modulo is an alias for Integer#%.
VALUE
rb_int_and(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_and(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_and(x, y);
}
return Qnil;
}
VALUE
rb_int_mul(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_mul(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_mul(x, y);
}
return rb_num_coerce_bin(x, y, '*');
}
Performs multiplication:
4 * 2 # => 8 4 * -2 # => -8 -4 * 2 # => -8 4 * 2.0 # => 8.0 4 * Rational(1, 3) # => (4/3) 4 * Complex(2, 0) # => (8+0i)
VALUE
rb_int_pow(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_pow(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_pow(x, y);
}
return Qnil;
}
Raises self to the power of numeric:
2 ** 3 # => 8 2 ** -3 # => (1/8) -2 ** 3 # => -8 -2 ** -3 # => (-1/8) 2 ** 3.3 # => 9.849155306759329 2 ** Rational(3, 1) # => (8/1) 2 ** Complex(3, 0) # => (8+0i)
VALUE
rb_int_plus(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_plus(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_plus(x, y);
}
return rb_num_coerce_bin(x, y, '+');
}
Performs addition:
2 + 2 # => 4 -2 + 2 # => 0 -2 + -2 # => -4 2 + 2.0 # => 4.0 2 + Rational(2, 1) # => (4/1) 2 + Complex(2, 0) # => (4+0i)
VALUE
rb_int_minus(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_minus(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_minus(x, y);
}
return rb_num_coerce_bin(x, y, '-');
}
Performs subtraction:
4 - 2 # => 2 -4 - 2 # => -6 -4 - -2 # => -2 4 - 2.0 # => 2.0 4 - Rational(2, 1) # => (2/1) 4 - Complex(2, 0) # => (2+0i)
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 88
def -@
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_uminus(self)'
end
Returns int, negated.
VALUE
rb_int_div(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_div(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_div(x, y);
}
return Qnil;
}
Performs division; for integer numeric, truncates the result to an integer:
4 / 3 # => 1 4 / -3 # => -2 -4 / 3 # => -2 -4 / -3 # => 1 For other +numeric+, returns non-integer result: 4 / 3.0 # => 1.3333333333333333 4 / Rational(3, 1) # => (4/3) 4 / Complex(3, 0) # => ((4/3)+0i)
static VALUE
int_lt(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_lt(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_lt(x, y);
}
return Qnil;
}
Returns true if the value of self is less than that of other:
1 < 0 # => false 1 < 1 # => false 1 < 2 # => true 1 < 0.5 # => false 1 < Rational(1, 2) # => false Raises an exception if the comparison cannot be made.
VALUE
rb_int_lshift(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return rb_fix_lshift(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_lshift(x, y);
}
return Qnil;
}
Returns self with bits shifted count positions to the left, or to the right if count is negative:
n = 0b11110000 "%08b" % (n << 1) # => "111100000" "%08b" % (n << 3) # => "11110000000" "%08b" % (n << -1) # => "01111000" "%08b" % (n << -3) # => "00011110"
Related: Integer#>>.
static VALUE
int_le(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_le(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_le(x, y);
}
return Qnil;
}
Returns true if the value of self is less than or equal to that of other:
1 <= 0 # => false 1 <= 1 # => true 1 <= 2 # => true 1 <= 0.5 # => false 1 <= Rational(1, 2) # => false
Raises an exception if the comparison cannot be made.
VALUE
rb_int_cmp(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_cmp(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_cmp(x, y);
}
else {
rb_raise(rb_eNotImpError, "need to define `<=>' in %s", rb_obj_classname(x));
}
}
Returns:
-
-1, if
selfis less thanother. -
0, if
selfis equal toother. -
1, if
selfis greater thenother. -
nil, ifselfandotherare incomparable.
Examples:
1 <=> 2 # => -1 1 <=> 1 # => 0 1 <=> 0 # => 1 1 <=> 'foo' # => nil 1 <=> 1.0 # => 0 1 <=> Rational(1, 1) # => 0 1 <=> Complex(1, 0) # => 0
This method is the basis for comparisons in module Comparable.
VALUE
rb_int_equal(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_equal(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_eq(x, y);
}
return Qnil;
}
Returns true if self is numerically equal to other; false otherwise.
1 == 2 #=> false 1 == 1.0 #=> true
Related: Integer#eql? (requires other to be an Integer).
Integer#=== is an alias for Integer#==.
VALUE
rb_int_gt(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_gt(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_gt(x, y);
}
return Qnil;
}
Returns true if the value of self is greater than that of other:
1 > 0 # => true 1 > 1 # => false 1 > 2 # => false 1 > 0.5 # => true 1 > Rational(1, 2) # => true Raises an exception if the comparison cannot be made.
VALUE
rb_int_ge(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_ge(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_ge(x, y);
}
return Qnil;
}
Returns true if the value of self is greater than or equal to that of other:
1 >= 0 # => true 1 >= 1 # => true 1 >= 2 # => false 1 >= 0.5 # => true 1 >= Rational(1, 2) # => true
Raises an exception if the comparison cannot be made.
static VALUE
rb_int_rshift(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return rb_fix_rshift(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_rshift(x, y);
}
return Qnil;
}
Returns self with bits shifted count positions to the right, or to the left if count is negative:
n = 0b11110000 "%08b" % (n >> 1) # => "01111000" "%08b" % (n >> 3) # => "00011110" "%08b" % (n >> -1) # => "111100000" "%08b" % (n >> -3) # => "11110000000"
Related: Integer#<<.
static VALUE
int_aref(int const argc, VALUE * const argv, VALUE const num)
{
rb_check_arity(argc, 1, 2);
if (argc == 2) {
return int_aref2(num, argv[0], argv[1]);
}
return int_aref1(num, argv[0]);
return Qnil;
}
Returns a slice of bits from self.
With argument offset, returns the bit at the given offset, where offset 0 refers to the least significant bit:
n = 0b10 # => 2 n[0] # => 0 n[1] # => 1 n[2] # => 0 n[3] # => 0
In principle, n[i] is equivalent to (n >> i) & 1. Thus, negative index always returns zero:
255[-1] # => 0
With arguments offset and size, returns size bits from self, beginning at offset and including bits of greater significance:
n = 0b111000 # => 56 "%010b" % n[0, 10] # => "0000111000" "%010b" % n[4, 10] # => "0000000011"
With argument range, returns range.size bits from self, beginning at range.begin and including bits of greater significance:
n = 0b111000 # => 56 "%010b" % n[0..9] # => "0000111000" "%010b" % n[4..9] # => "0000000011"
Raises an exception if the slice cannot be constructed.
static VALUE
int_xor(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_xor(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_xor(x, y);
}
return Qnil;
}
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 120
def abs
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_abs(self)'
end
Returns the absolute value of int.
(-12345).abs #=> 12345 -12345.abs #=> 12345 12345.abs #=> 12345
Integer#magnitude is an alias for Integer#abs.
static VALUE
int_allbits_p(VALUE num, VALUE mask)
{
mask = rb_to_int(mask);
return rb_int_equal(rb_int_and(num, mask), mask);
}
Returns true if all bits that are set (=1) in mask are also set in self; returns false otherwise.
Example values:
0b1010101 self
0b1010100 mask
0b1010100 self & mask
true self.allbits?(mask)
0b1010100 self
0b1010101 mask
0b1010100 self & mask
false self.allbits?(mask)
Related: Integer#anybits?, Integer#nobits?.
static VALUE
int_anybits_p(VALUE num, VALUE mask)
{
mask = rb_to_int(mask);
return RBOOL(!int_zero_p(rb_int_and(num, mask)));
}
Returns true if any bit that is set (=1) in mask is also set in self; returns false otherwise.
Example values:
0b10000010 self
0b11111111 mask
0b10000010 self & mask
true self.anybits?(mask)
0b00000000 self
0b11111111 mask
0b00000000 self & mask
false self.anybits?(mask)
Related: Integer#allbits?, Integer#nobits?.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 166
def bit_length
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_bit_length(self)'
end
Returns the number of bits of the value of int.
“Number of bits” means the bit position of the highest bit which is different from the sign bit (where the least significant bit has bit position 1). If there is no such bit (zero or minus one), zero is returned.
I.e. this method returns ceil(log2(int < 0 ? -int : int+1)).
(-2**1000-1).bit_length #=> 1001 (-2**1000).bit_length #=> 1000 (-2**1000+1).bit_length #=> 1000 (-2**12-1).bit_length #=> 13 (-2**12).bit_length #=> 12 (-2**12+1).bit_length #=> 12 -0x101.bit_length #=> 9 -0x100.bit_length #=> 8 -0xff.bit_length #=> 8 -2.bit_length #=> 1 -1.bit_length #=> 0 0.bit_length #=> 0 1.bit_length #=> 1 0xff.bit_length #=> 8 0x100.bit_length #=> 9 (2**12-1).bit_length #=> 12 (2**12).bit_length #=> 13 (2**12+1).bit_length #=> 13 (2**1000-1).bit_length #=> 1000 (2**1000).bit_length #=> 1001 (2**1000+1).bit_length #=> 1001
This method can be used to detect overflow in Array#pack as follows:
if n.bit_length < 32 [n].pack("l") # no overflow else raise "overflow" end
static VALUE
int_ceil(int argc, VALUE* argv, VALUE num)
{
int ndigits;
if (!rb_check_arity(argc, 0, 1)) return num;
ndigits = NUM2INT(argv[0]);
if (ndigits >= 0) {
return num;
}
return rb_int_ceil(num, ndigits);
}
Returns the smallest number greater than or equal to self with a precision of ndigits decimal digits.
When the precision is negative, the returned value is an integer with at least ndigits.abs trailing zeros:
555.ceil(-1) # => 560 555.ceil(-2) # => 600 -555.ceil(-2) # => -500 555.ceil(-3) # => 1000
Returns self when ndigits is zero or positive.
555.ceil # => 555 555.ceil(50) # => 555
Related: Integer#floor.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 280
def ceildiv(other)
-div(-other)
end
Returns the result of division self by other. The result is rounded up to the nearest integer.
3.ceildiv(3) # => 1 4.ceildiv(3) # => 2 4.ceildiv(-3) # => -1 -4.ceildiv(3) # => -1 -4.ceildiv(-3) # => 2 3.ceildiv(1.2) # => 3
static VALUE
int_chr(int argc, VALUE *argv, VALUE num)
{
char c;
unsigned int i;
rb_encoding *enc;
if (rb_num_to_uint(num, &i) == 0) {
}
else if (FIXNUM_P(num)) {
rb_raise(rb_eRangeError, "%ld out of char range", FIX2LONG(num));
}
else {
rb_raise(rb_eRangeError, "bignum out of char range");
}
switch (argc) {
case 0:
if (0xff < i) {
enc = rb_default_internal_encoding();
if (!enc) {
rb_raise(rb_eRangeError, "%u out of char range", i);
}
goto decode;
}
c = (char)i;
if (i < 0x80) {
return rb_usascii_str_new(&c, 1);
}
else {
return rb_str_new(&c, 1);
}
case 1:
break;
default:
rb_error_arity(argc, 0, 1);
}
enc = rb_to_encoding(argv[0]);
if (!enc) enc = rb_ascii8bit_encoding();
decode:
return rb_enc_uint_chr(i, enc);
}
Returns a 1-character string containing the character represented by the value of self, according to the given encoding.
65.chr # => "A" 0.chr # => "\x00" 255.chr # => "\xFF" string = 255.chr(Encoding::UTF_8) string.encoding # => Encoding::UTF_8
Raises an exception if self is negative.
Related: Integer#ord.
static VALUE
rb_int_coerce(VALUE x, VALUE y)
{
if (RB_INTEGER_TYPE_P(y)) {
return rb_assoc_new(y, x);
}
else {
x = rb_Float(x);
y = rb_Float(y);
return rb_assoc_new(y, x);
}
}
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 300
def denominator
1
end
Returns 1.
static VALUE
rb_int_digits(int argc, VALUE *argv, VALUE num)
{
VALUE base_value;
long base;
if (rb_num_negative_p(num))
rb_raise(rb_eMathDomainError, "out of domain");
if (rb_check_arity(argc, 0, 1)) {
base_value = rb_to_int(argv[0]);
if (!RB_INTEGER_TYPE_P(base_value))
rb_raise(rb_eTypeError, "wrong argument type %s (expected Integer)",
rb_obj_classname(argv[0]));
if (RB_BIGNUM_TYPE_P(base_value))
return rb_int_digits_bigbase(num, base_value);
base = FIX2LONG(base_value);
if (base < 0)
rb_raise(rb_eArgError, "negative radix");
else if (base < 2)
rb_raise(rb_eArgError, "invalid radix %ld", base);
}
else
base = 10;
if (FIXNUM_P(num))
return rb_fix_digits(num, base);
else if (RB_BIGNUM_TYPE_P(num))
return rb_int_digits_bigbase(num, LONG2FIX(base));
return Qnil;
}
Returns an array of integers representing the base-radix digits of self; the first element of the array represents the least significant digit:
12345.digits # => [5, 4, 3, 2, 1] 12345.digits(7) # => [4, 6, 6, 0, 5] 12345.digits(100) # => [45, 23, 1]
Raises an exception if self is negative or base is less than 2.
VALUE
rb_int_idiv(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_idiv(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_idiv(x, y);
}
return num_div(x, y);
}
Performs integer division; returns the integer result of dividing self by numeric:
4.div(3) # => 1 4.div(-3) # => -2 -4.div(3) # => -2 -4.div(-3) # => 1 4.div(3.0) # => 1 4.div(Rational(3, 1)) # => 1 Raises an exception if +numeric+ does not have method +div+.
VALUE
rb_int_divmod(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_divmod(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_divmod(x, y);
}
return Qnil;
}
Returns a 2-element array [q, r], where
q = (self/other).floor # Quotient r = self % other # Remainder
Examples:
11.divmod(4) # => [2, 3] 11.divmod(-4) # => [-3, -1] -11.divmod(4) # => [-3, 1] -11.divmod(-4) # => [2, -3] 12.divmod(4) # => [3, 0] 12.divmod(-4) # => [-3, 0] -12.divmod(4) # => [-3, 0] -12.divmod(-4) # => [3, 0] 13.divmod(4.0) # => [3, 1.0] 13.divmod(Rational(4, 1)) # => [3, (1/1)]
static VALUE
int_downto(VALUE from, VALUE to)
{
RETURN_SIZED_ENUMERATOR(from, 1, &to, int_downto_size);
if (FIXNUM_P(from) && FIXNUM_P(to)) {
long i, end;
end = FIX2LONG(to);
for (i=FIX2LONG(from); i >= end; i--) {
rb_yield(LONG2FIX(i));
}
}
else {
VALUE i = from, c;
while (!(c = rb_funcall(i, '<', 1, to))) {
rb_yield(i);
i = rb_funcall(i, '-', 1, INT2FIX(1));
}
if (NIL_P(c)) rb_cmperr(i, to);
}
return from;
}
Calls the given block with each integer value from self down to limit; returns self:
a = [] 10.downto(5) {|i| a << i } # => 10 a # => [10, 9, 8, 7, 6, 5] a = [] 0.downto(-5) {|i| a << i } # => 0 a # => [0, -1, -2, -3, -4, -5] 4.downto(5) {|i| fail 'Cannot happen' } # => 4
With no block given, returns an Enumerator.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 175
def even?
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_even_p(self)'
end
Returns true if int is an even number.
VALUE
rb_int_fdiv(VALUE x, VALUE y)
{
if (RB_INTEGER_TYPE_P(x)) {
return DBL2NUM(rb_int_fdiv_double(x, y));
}
return Qnil;
}
static VALUE
int_floor(int argc, VALUE* argv, VALUE num)
{
int ndigits;
if (!rb_check_arity(argc, 0, 1)) return num;
ndigits = NUM2INT(argv[0]);
if (ndigits >= 0) {
return num;
}
return rb_int_floor(num, ndigits);
}
Returns the largest number less than or equal to self with a precision of ndigits decimal digits.
When ndigits is negative, the returned value has at least ndigits.abs trailing zeros:
555.floor(-1) # => 550 555.floor(-2) # => 500 -555.floor(-2) # => -600 555.floor(-3) # => 0
Returns self when ndigits is zero or positive.
555.floor # => 555 555.floor(50) # => 555
Related: Integer#ceil.
VALUE
rb_gcd(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return f_gcd(self, other);
}
Returns the greatest common divisor of the two integers. The result is always positive. 0.gcd(x) and x.gcd(0) return x.abs.
36.gcd(60) #=> 12 2.gcd(2) #=> 2 3.gcd(-7) #=> 1 ((1<<31)-1).gcd((1<<61)-1) #=> 1
VALUE
rb_gcdlcm(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return rb_assoc_new(f_gcd(self, other), f_lcm(self, other));
}
Returns an array with the greatest common divisor and the least common multiple of the two integers, [gcd, lcm].
36.gcdlcm(60) #=> [12, 180] 2.gcdlcm(2) #=> [2, 2] 3.gcdlcm(-7) #=> [1, 21] ((1<<31)-1).gcdlcm((1<<61)-1) #=> [1, 4951760154835678088235319297]
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 184
def integer?
true
end
Since int is already an Integer, this always returns true.
VALUE
rb_lcm(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return f_lcm(self, other);
}
Returns the least common multiple of the two integers. The result is always positive. 0.lcm(x) and x.lcm(0) return zero.
36.lcm(60) #=> 180 2.lcm(2) #=> 2 3.lcm(-7) #=> 21 ((1<<31)-1).lcm((1<<61)-1) #=> 4951760154835678088235319297
static VALUE
int_nobits_p(VALUE num, VALUE mask)
{
mask = rb_to_int(mask);
return RBOOL(int_zero_p(rb_int_and(num, mask)));
}
Returns true if no bit that is set (=1) in mask is also set in self; returns false otherwise.
Example values:
0b11110000 self
0b00001111 mask
0b00000000 self & mask
true self.nobits?(mask)
0b00000001 self
0b11111111 mask
0b00000001 self & mask
false self.nobits?(mask)
Related: Integer#allbits?, Integer#anybits?.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 290
def numerator
self
end
Returns self.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 200
def odd?
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_odd_p(self)'
end
Returns true if int is an odd number.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 216
def ord
self
end
Returns the int itself.
97.ord #=> 97
This method is intended for compatibility to character literals in Ruby 1.9.
For example, ?a.ord returns 97 both in 1.8 and 1.9.
VALUE
rb_int_powm(int const argc, VALUE * const argv, VALUE const num)
{
rb_check_arity(argc, 1, 2);
if (argc == 1) {
return rb_int_pow(num, argv[0]);
}
else {
VALUE const a = num;
VALUE const b = argv[0];
VALUE m = argv[1];
int nega_flg = 0;
if ( ! RB_INTEGER_TYPE_P(b)) {
rb_raise(rb_eTypeError, "Integer#pow() 2nd argument not allowed unless a 1st argument is integer");
}
if (rb_int_negative_p(b)) {
rb_raise(rb_eRangeError, "Integer#pow() 1st argument cannot be negative when 2nd argument specified");
}
if (!RB_INTEGER_TYPE_P(m)) {
rb_raise(rb_eTypeError, "Integer#pow() 2nd argument not allowed unless all arguments are integers");
}
if (rb_int_negative_p(m)) {
m = rb_int_uminus(m);
nega_flg = 1;
}
if (FIXNUM_P(m)) {
long const half_val = (long)HALF_LONG_MSB;
long const mm = FIX2LONG(m);
if (!mm) rb_num_zerodiv();
if (mm == 1) return INT2FIX(0);
if (mm <= half_val) {
return int_pow_tmp1(rb_int_modulo(a, m), b, mm, nega_flg);
}
else {
return int_pow_tmp2(rb_int_modulo(a, m), b, mm, nega_flg);
}
}
else {
if (rb_bigzero_p(m)) rb_num_zerodiv();
if (bignorm(m) == INT2FIX(1)) return INT2FIX(0);
return int_pow_tmp3(rb_int_modulo(a, m), b, m, nega_flg);
}
}
UNREACHABLE_RETURN(Qnil);
}
Returns (modular) exponentiation as:
a.pow(b) #=> same as a**b a.pow(b, m) #=> same as (a**b) % m, but avoids huge temporary values
static VALUE
rb_int_pred(VALUE num)
{
if (FIXNUM_P(num)) {
long i = FIX2LONG(num) - 1;
return LONG2NUM(i);
}
if (RB_BIGNUM_TYPE_P(num)) {
return rb_big_minus(num, INT2FIX(1));
}
return num_funcall1(num, '-', INT2FIX(1));
}
Returns the predecessor of self (equivalent to self - 1):
1.pred #=> 0 -1.pred #=> -2
Related: Integer#succ (successor value).
static VALUE
integer_rationalize(int argc, VALUE *argv, VALUE self)
{
rb_check_arity(argc, 0, 1);
return integer_to_r(self);
}
Returns the value as a rational. The optional argument eps is always ignored.
static VALUE
int_remainder(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return num_remainder(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_remainder(x, y);
}
return Qnil;
}
Returns the remainder after dividing self by other.
Examples:
11.remainder(4) # => 3 11.remainder(-4) # => 3 -11.remainder(4) # => -3 -11.remainder(-4) # => -3 12.remainder(4) # => 0 12.remainder(-4) # => 0 -12.remainder(4) # => 0 -12.remainder(-4) # => 0 13.remainder(4.0) # => 1.0 13.remainder(Rational(4, 1)) # => (1/1)
static VALUE
int_round(int argc, VALUE* argv, VALUE num)
{
int ndigits;
int mode;
VALUE nd, opt;
if (!rb_scan_args(argc, argv, "01:", &nd, &opt)) return num;
ndigits = NUM2INT(nd);
mode = rb_num_get_rounding_option(opt);
if (ndigits >= 0) {
return num;
}
return rb_int_round(num, ndigits, mode);
}
Returns self rounded to the nearest value with a precision of ndigits decimal digits.
When ndigits is negative, the returned value has at least ndigits.abs trailing zeros:
555.round(-1) # => 560 555.round(-2) # => 600 555.round(-3) # => 1000 -555.round(-2) # => -600 555.round(-4) # => 0
Returns self when ndigits is zero or positive.
555.round # => 555 555.round(1) # => 555 555.round(50) # => 555
If keyword argument half is given, and self is equidistant from the two candidate values, the rounding is according to the given half value:
-
:upornil: round away from zero:25.round(-1, half: :up) # => 30 (-25).round(-1, half: :up) # => -30
-
:down: round toward zero:25.round(-1, half: :down) # => 20 (-25).round(-1, half: :down) # => -20
-
:even: round toward the candidate whose last nonzero digit is even:25.round(-1, half: :even) # => 20 15.round(-1, half: :even) # => 20 (-25).round(-1, half: :even) # => -20
Raises and exception if the value for half is invalid.
Related: Integer#truncate.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 235
def size
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_size(self)'
end
Document-method: Integer#size
Returns the number of bytes in the machine representation of int (machine dependent).
1.size #=> 8 -1.size #=> 8 2147483647.size #=> 8 (256**10 - 1).size #=> 10 (256**20 - 1).size #=> 20 (256**40 - 1).size #=> 40
VALUE
rb_int_succ(VALUE num)
{
if (FIXNUM_P(num)) {
long i = FIX2LONG(num) + 1;
return LONG2NUM(i);
}
if (RB_BIGNUM_TYPE_P(num)) {
return rb_big_plus(num, INT2FIX(1));
}
return num_funcall1(num, '+', INT2FIX(1));
}
Returns the successor integer of self (equivalent to self + 1):
1.succ #=> 2 -1.succ #=> 0
Integer#next is an alias for Integer#succ.
Related: Integer#pred (predecessor value).
static VALUE
int_dotimes(VALUE num)
{
RETURN_SIZED_ENUMERATOR(num, 0, 0, int_dotimes_size);
if (FIXNUM_P(num)) {
long i, end;
end = FIX2LONG(num);
for (i=0; i<end; i++) {
rb_yield_1(LONG2FIX(i));
}
}
else {
VALUE i = INT2FIX(0);
for (;;) {
if (!RTEST(int_le(i, num))) break;
rb_yield(i);
i = rb_int_plus(i, INT2FIX(1));
}
}
return num;
}
Calls the given block self times with each integer in (0..self-1):
a = [] 5.times {|i| a.push(i) } # => 5 a # => [0, 1, 2, 3, 4]
With no block given, returns an Enumerator.
# File tmp/rubies/ruby-3.2.0/ext/openssl/lib/openssl/bn.rb, line 37
def to_bn
OpenSSL::BN::new(self)
end
Casts an Integer as an OpenSSL::BN
See ‘man bn` for more info.
# File tmp/rubies/ruby-3.2.0/ext/bigdecimal/lib/bigdecimal/util.rb, line 23
def to_d
BigDecimal(self)
end
Returns the value of int as a BigDecimal.
require 'bigdecimal' require 'bigdecimal/util' 42.to_d # => 0.42e2
See also BigDecimal::new.
static VALUE
int_to_f(VALUE num)
{
double val;
if (FIXNUM_P(num)) {
val = (double)FIX2LONG(num);
}
else if (RB_BIGNUM_TYPE_P(num)) {
val = rb_big2dbl(num);
}
else {
rb_raise(rb_eNotImpError, "Unknown subclass for to_f: %s", rb_obj_classname(num));
}
return DBL2NUM(val);
}
Converts self to a Float:
1.to_f # => 1.0 -1.to_f # => -1.0
If the value of self does not fit in a Float, the result is infinity:
(10**400).to_f # => Infinity (-10**400).to_f # => -Infinity
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 246
def to_i
self
end
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 254
def to_int
self
end
Since int is already an Integer, returns self.
static VALUE
integer_to_r(VALUE self)
{
return rb_rational_new1(self);
}
Returns the value as a rational.
1.to_r #=> (1/1) (1<<64).to_r #=> (18446744073709551616/1)
MJIT_FUNC_EXPORTED VALUE
rb_int_to_s(int argc, VALUE *argv, VALUE x)
{
int base;
if (rb_check_arity(argc, 0, 1))
base = NUM2INT(argv[0]);
else
base = 10;
return rb_int2str(x, base);
}
Returns a string containing the place-value representation of self in radix base (in 2..36).
12345.to_s # => "12345" 12345.to_s(2) # => "11000000111001" 12345.to_s(8) # => "30071" 12345.to_s(10) # => "12345" 12345.to_s(16) # => "3039" 12345.to_s(36) # => "9ix" 78546939656932.to_s(36) # => "rubyrules"
Raises an exception if base is out of range.
Integer#inspect is an alias for Integer#to_s.
static VALUE
int_truncate(int argc, VALUE* argv, VALUE num)
{
int ndigits;
if (!rb_check_arity(argc, 0, 1)) return num;
ndigits = NUM2INT(argv[0]);
if (ndigits >= 0) {
return num;
}
return rb_int_truncate(num, ndigits);
}
Returns self truncated (toward zero) to a precision of ndigits decimal digits.
When ndigits is negative, the returned value has at least ndigits.abs trailing zeros:
555.truncate(-1) # => 550 555.truncate(-2) # => 500 -555.truncate(-2) # => -500
Returns self when ndigits is zero or positive.
555.truncate # => 555 555.truncate(50) # => 555
Related: Integer#round.
static VALUE
int_upto(VALUE from, VALUE to)
{
RETURN_SIZED_ENUMERATOR(from, 1, &to, int_upto_size);
if (FIXNUM_P(from) && FIXNUM_P(to)) {
long i, end;
end = FIX2LONG(to);
for (i = FIX2LONG(from); i <= end; i++) {
rb_yield(LONG2FIX(i));
}
}
else {
VALUE i = from, c;
while (!(c = rb_funcall(i, '>', 1, to))) {
rb_yield(i);
i = rb_funcall(i, '+', 1, INT2FIX(1));
}
ensure_cmp(c, i, to);
}
return from;
}
Calls the given block with each integer value from self up to limit; returns self:
a = [] 5.upto(10) {|i| a << i } # => 5 a # => [5, 6, 7, 8, 9, 10] a = [] -5.upto(0) {|i| a << i } # => -5 a # => [-5, -4, -3, -2, -1, 0] 5.upto(4) {|i| fail 'Cannot happen' } # => 5
With no block given, returns an Enumerator.
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 262
def zero?
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_zero_p(self)'
end
Returns true if int has a zero value.
static VALUE
int_or(VALUE x, VALUE y)
{
if (FIXNUM_P(x)) {
return fix_or(x, y);
}
else if (RB_BIGNUM_TYPE_P(x)) {
return rb_big_or(x, y);
}
return Qnil;
}
# File tmp/rubies/ruby-3.2.0/numeric.rb, line 104
def ~
Primitive.attr! 'inline'
Primitive.cexpr! 'rb_int_comp(self)'
end
One’s complement: returns a number where each bit is flipped.
Inverts the bits in an Integer. As integers are conceptually of infinite length, the result acts as if it had an infinite number of one bits to the left. In hex representations, this is displayed as two periods to the left of the digits.
sprintf("%X", ~0x1122334455) #=> "..FEEDDCCBBAA"