Class: Bitset

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/bitset.rb,
ext/bitset/bitset.c

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(len) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 50

static VALUE rb_bitset_initialize(VALUE self, VALUE len) {
    Bitset * bs = get_bitset(self);
    bitset_setup(bs, NUM2INT(len));
    return self;
}

Class Method Details

.from_s(s) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 303

static VALUE rb_bitset_from_s(VALUE self, VALUE s) {
    int length = RSTRING_LEN(s);
    char* data = StringValuePtr(s);
    Bitset * new_bs = bitset_new();
    int i;

    bitset_setup(new_bs, length);

    for (i = 0; i < length; i++) {
        if (data[i] == '1') {
            _set_bit(new_bs, i);
        }
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

.unpack(str) ⇒ Object

Convert a string created using the pack method back into a bitset.



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# File 'lib/bitset.rb', line 19

def self.unpack str
  bits = str.unpack("b*")[0]
  padding_bits = bits[0...3].to_i(2)
  from_s(bits[3 .. -1 - padding_bits])
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 525

static VALUE rb_bitset_equal(VALUE self, VALUE other) {
    int i;
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);
    int max = INTS(bs);

    if (bs->len != other_bs->len)
       return Qfalse;
    for(i = 0; i < max; i++) {
       if (bs->data[i] != other_bs->data[i]) {
          return Qfalse;
       }
    }
    return Qtrue;
}

#[](index) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 93

static VALUE rb_bitset_aref(VALUE self, VALUE index) {
    Bitset * bs = get_bitset(self);
    int idx = NUM2INT(index);
    validate_index(bs, idx);
    return _get_bit(bs, idx) > 0 ? Qtrue : Qfalse;
}

#[]=(index, value) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 100

static VALUE rb_bitset_aset(VALUE self, VALUE index, VALUE value) {
    Bitset * bs = get_bitset(self);
    int idx = NUM2INT(index);
    validate_index(bs, idx);
    assign_bit(bs, idx, value);
    return Qtrue;
}

#cardinality ⇒ Object 



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# File 'ext/bitset/bitset.c', line 188

static VALUE rb_bitset_cardinality(VALUE self) {
    Bitset * bs = get_bitset(self);
    return INT2NUM(cardinality(bs));
}

#clear(*args) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 130

static VALUE rb_bitset_clear(int argc, VALUE * argv, VALUE self) {
    int i;
    Bitset * bs = get_bitset(self);

    if (argc == 1 && rb_obj_is_kind_of(argv[0], rb_const_get(rb_cObject, rb_intern("Array")))) {
        for(i = 0; i < RARRAY_LEN(argv[0]); i++) {
            VALUE index = RARRAY_PTR(argv[0])[i];
            int idx = NUM2INT(index);
            validate_index(bs, idx);
            _clear_bit(bs, idx);
        }
    } else {
        for(i = 0; i < argc; i++) {
            VALUE index = argv[i];
            int idx = NUM2INT(index);
            validate_index(bs, idx);
            _clear_bit(bs, idx);
        }
    }
    return Qtrue;
}

#clear?(*args) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'ext/bitset/bitset.c', line 152

static VALUE rb_bitset_clear_p(int argc, VALUE * argv, VALUE self) {
    int i;
    Bitset * bs = get_bitset(self);
    for(i = 0; i < argc; i++) {
        VALUE index = argv[i];
        int idx = NUM2INT(index);
        validate_index(bs, idx);
        if(_get_bit(bs, idx) > 0)
            return Qfalse;
    }
    return Qtrue;
}

#difference(other) ⇒ Object Also known as: - 



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# File 'ext/bitset/bitset.c', line 233

static VALUE rb_bitset_difference(VALUE self, VALUE other) {
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);
    Bitset * new_bs;
    int max = INTS(bs);
    int i;

    verify_equal_size(bs, other_bs);
    new_bs = bitset_new();
    bitset_setup(new_bs, bs->len);

    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        uint64_t other_segment = other_bs->data[i];
        new_bs->data[i] = segment & ~other_segment;
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#difference!(other) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 575

static VALUE rb_bitset_difference_mutable(VALUE self, VALUE other) {
    return mutable(self, other, &difference);
}

#dup ⇒ Object Also known as: clone 



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# File 'ext/bitset/bitset.c', line 384

static VALUE rb_bitset_dup(VALUE self) {
    Bitset * bs = get_bitset(self);
    int max = INTS(bs);

    Bitset * new_bs = bitset_new();
    bitset_setup(new_bs, bs->len);

    memcpy(new_bs->data, bs->data, max * sizeof(bs->data[0]));
    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#each ⇒ Object 



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# File 'ext/bitset/bitset.c', line 336

static VALUE rb_bitset_each(VALUE self) {
    Bitset * bs = get_bitset(self);
    int i;

    for(i = 0; i < bs->len; i++) {
        rb_yield(_get_bit(bs, i) ? Qtrue : Qfalse);
    }

    return self;
}

#each_set(*args) ⇒ Object Also known as: to_a

Yield the bit numbers of each set bit in sequence to a block. If

there is no block, return an array of those numbers.



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# File 'ext/bitset/bitset.c', line 397

static VALUE rb_bitset_each_set(int argc, VALUE * argv,  VALUE self) {
    Bitset * bs = get_bitset(self);
    int seg_no;
    int max = INTS(bs);
    uint64_t* seg_ptr = bs->data;
    int block_p = rb_block_given_p();
    VALUE ary = Qnil;
    int set_bit_no = -1;

    /* If there is one argument, it is an index into the notional
       output array, and return an int. If there are two arguments,
       return up to <n> arguments where is the second argument. */
    int min_set_bit_no = (argc > 0) ? NUM2INT(argv[0]) : 0;
    int max_set_bit_no;

    if (argc > 2) {
       VALUE error = rb_const_get(rb_cObject, rb_intern("ArgumentError"));
       rb_raise(error, "wrong number of arguments (given %d, expected 0..2)",
                argc);
    }

    if (min_set_bit_no < 0) {
        /* Convert negative numbers into offsets from the end of the array. */
        min_set_bit_no = cardinality(bs) + min_set_bit_no;
    }

    max_set_bit_no = (argc == 0)
        ? INT_MAX
        : (argc == 1)
        ? (min_set_bit_no + 1)
        : (min_set_bit_no + NUM2INT(argv[1]));

    if (min_set_bit_no < 0 || max_set_bit_no < min_set_bit_no)
        return Qnil;

    if (argc != 1 && !block_p) {
       ary = rb_ary_new();
    }
    if (min_set_bit_no < 0 || max_set_bit_no < min_set_bit_no)
        return Qnil;

    for (seg_no = 0; seg_no < max; ++seg_no, ++seg_ptr) {
       uint64_t segment = *seg_ptr;
       int bit_position = 0;
       bool finished = false;
       while (segment) {
          VALUE v;

          if (!(segment & 1)) {
             int shift = psnip_builtin_ctz64(segment);
             bit_position += shift;
             segment >>= shift;
          }
          v = INT2NUM(_seg_no_to_bit_no(seg_no) + bit_position);
          ++bit_position;
          segment >>= 1;
          ++set_bit_no;
          if (set_bit_no < min_set_bit_no) {
             continue;
          }
          if (set_bit_no >= max_set_bit_no) {
              finished = true;
             break;
          }
          if (block_p) {
             rb_yield(v);
          } else if (argc == 1) {
              return v;
          } else {
             rb_ary_push(ary, v);
          }
       }
       if (finished) {
           break;
       }
    }

    return block_p ? self : ary;
}

#empty? ⇒ Boolean

#each_set allows an optional block, and #to_a normally doesn’t.

But an alias is simpler than having two different functions.

Returns:

  • (Boolean) 


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# File 'ext/bitset/bitset.c', line 477

static VALUE rb_bitset_empty_p(VALUE self) {
    Bitset * bs = get_bitset(self);
    int seg_no;
    int max = INTS(bs);
    uint64_t* seg_ptr = bs->data;

    for (seg_no = 0; seg_no < max; ++seg_no, ++seg_ptr) {
       if (*seg_ptr) {
          return Qfalse;
       }
    }
    return Qtrue;
}

#hamming(other) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 320

static VALUE rb_bitset_hamming(VALUE self, VALUE other) {
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);

    int max = INTS(bs);
    int count = 0;
    int i;
    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        uint64_t other_segment = other_bs->data[i];
        count += psnip_builtin_popcount64(segment ^ other_segment);
    }

    return INT2NUM(count);
}

#intersect(other) ⇒ Object Also known as: &, and 



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# File 'ext/bitset/bitset.c', line 193

static VALUE rb_bitset_intersect(VALUE self, VALUE other) {
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);
    Bitset * new_bs;
    int max = INTS(bs);
    int i;

    verify_equal_size(bs, other_bs);
    new_bs = bitset_new();
    bitset_setup(new_bs, bs->len);

    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        uint64_t other_segment = other_bs->data[i];
        new_bs->data[i] = segment & other_segment;
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#intersect!(other) ⇒ Object Also known as: and! 



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# File 'ext/bitset/bitset.c', line 567

static VALUE rb_bitset_intersect_mutable(VALUE self, VALUE other) {
    return mutable(self, other, &and);
}

#marshal_dump ⇒ Object 



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# File 'ext/bitset/bitset.c', line 347

static VALUE rb_bitset_marshall_dump(VALUE self) {
    Bitset * bs = get_bitset(self);
    VALUE hash = rb_hash_new();
    VALUE data = rb_str_new((const char *) bs->data, BYTES(bs));

    rb_hash_aset(hash, ID2SYM(rb_intern("len")), UINT2NUM(bs->len));
    rb_hash_aset(hash, ID2SYM(rb_intern("data")), data);

    return hash;
}

#marshal_load(hash) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 358

static VALUE rb_bitset_marshall_load(VALUE self, VALUE hash) {
    Bitset * bs = get_bitset(self);
    int len = NUM2INT(rb_hash_aref(hash, ID2SYM(rb_intern("len"))));

    VALUE data = rb_hash_aref(hash, ID2SYM(rb_intern("data")));

    bitset_setup(bs, len);

    bs->data = (uint64_t *) calloc(INTS(bs), sizeof(uint64_t));
    memcpy(bs->data, RSTRING_PTR(data), BYTES(bs));

    return Qnil;
}

#not ⇒ Object Also known as: ~ 



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# File 'ext/bitset/bitset.c', line 273

static VALUE rb_bitset_not(VALUE self) {
    Bitset * bs = get_bitset(self);
    Bitset * new_bs = bitset_new();
    int max = INTS(bs);
    int i;

    bitset_setup(new_bs, bs->len);
    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        new_bs->data[i] = ~segment;
    }
    if(_bit_no(bs->len) != 0)
        new_bs->data[max-1] &= _bit_mask(bs->len) - 1;

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#pack ⇒ Object

You could make a good case that this is redundant with Marshal.dump and Marshal.load, but it does save a few bytes.



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# File 'lib/bitset.rb', line 11

def pack
  # Number of bits of zero padding in this representation.
  padding_bits = (size+3) & 7
  padding_bits = (padding_bits == 0) ? 0 : (8 - padding_bits)
  [("%03b" % padding_bits) + self.to_s].pack("b*")
end

#reset! ⇒ Object 



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# File 'ext/bitset/bitset.c', line 579

static VALUE rb_bitset_reset(VALUE self) {
    Bitset * bs = get_bitset(self);
    memset(bs->data, 0, (INTS(bs) * sizeof(uint64_t)) );
    return self;
}

#reverse(index_array) ⇒ Object

This could run a bit faster if you worked at it.



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# File 'ext/bitset/bitset.c', line 510

static VALUE rb_bitset_reverse(VALUE self, VALUE index_array) {
    int i;
    Bitset * bs = get_bitset(self);
    int len = bs->len;
    Bitset * new_bs = bitset_new();
    bitset_setup(new_bs, len);
    for (i = 0; i < len; ++i) {
       if (_get_bit(bs, i)) {
          _set_bit(new_bs, len - i - 1);
       }
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#set(*args) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 108

static VALUE rb_bitset_set(int argc, VALUE * argv, VALUE self) {
    int i;
    Bitset * bs = get_bitset(self);

    if (argc == 1 && rb_obj_is_kind_of(argv[0], rb_const_get(rb_cObject, rb_intern("Array")))) {
        for(i = 0; i < RARRAY_LEN(argv[0]); i++) {
            VALUE index = RARRAY_PTR(argv[0])[i];
            int idx = NUM2INT(index);
            validate_index(bs, idx);
            _set_bit(bs, idx);
        }
    } else {
        for(i = 0; i < argc; i++) {
            VALUE index = argv[i];
            int idx = NUM2INT(index);
            validate_index(bs, idx);
            _set_bit(bs, idx);
        }
    }
    return Qtrue;
}

#set?(*args) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'ext/bitset/bitset.c', line 165

static VALUE rb_bitset_set_p(int argc, VALUE * argv, VALUE self) {
    int i;
    Bitset * bs = get_bitset(self);
    for(i = 0; i < argc; i++) {
        VALUE index = argv[i];
        int idx = NUM2INT(index);
        validate_index(bs, idx);
        if(_get_bit(bs, idx) == 0)
            return Qfalse;
    }
    return Qtrue;
}

#size(len) ⇒ Object 



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# File 'ext/bitset/bitset.c', line 56

static VALUE rb_bitset_size(VALUE self, VALUE len) {
    Bitset * bs = get_bitset(self);
    return INT2NUM(bs->len);
}

#to_binary_array ⇒ Object 



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# File 'ext/bitset/bitset.c', line 372

static VALUE rb_bitset_to_binary_array(VALUE self) {
    Bitset * bs = get_bitset(self);
    int i;

    VALUE array = rb_ary_new2(bs->len / 2);
    for(i = 0; i < bs->len; i++) {
        rb_ary_push(array, INT2NUM(_get_bit(bs, i) > 0 ? 1 : 0));
    }

    return array;
}

#to_s ⇒ Object 



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# File 'ext/bitset/bitset.c', line 290

static VALUE rb_bitset_to_s(VALUE self) {
    Bitset * bs = get_bitset(self);

    int i;
    char * data = malloc(bs->len + 1);
    for(i = 0; i < bs->len; i++) {
        data[i] = _get_bit(bs, i)  ? '1' : '0';
    }
    data[bs->len] = 0;

    return rb_str_new2(data);
}

#union(other) ⇒ Object Also known as: |, or 



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# File 'ext/bitset/bitset.c', line 213

static VALUE rb_bitset_union(VALUE self, VALUE other) {
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);
    Bitset * new_bs;
    int max = INTS(bs);
    int i;

    verify_equal_size(bs, other_bs);
    new_bs = bitset_new();
    bitset_setup(new_bs, bs->len);

    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        uint64_t other_segment = other_bs->data[i];
        new_bs->data[i] = segment | other_segment;
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#union!(other) ⇒ Object Also known as: or! 



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# File 'ext/bitset/bitset.c', line 563

static VALUE rb_bitset_union_mutable(VALUE self, VALUE other) {
    return mutable(self, other, &or);
}

#values_at(index_array) ⇒ Object Also known as: select_bits 



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# File 'ext/bitset/bitset.c', line 491

static VALUE rb_bitset_values_at(VALUE self, VALUE index_array) {
    int i;
    Bitset * bs = get_bitset(self);
    int blen = bs->len;
    int alen = RARRAY_LEN(index_array);
    VALUE *ptr = RARRAY_PTR(index_array);
    Bitset * new_bs = bitset_new();
    bitset_setup(new_bs, alen);
    for (i = 0; i < alen; ++i) {
       int idx = NUM2INT(ptr[i]);
       if (idx >= 0 && idx < blen && _get_bit(bs, idx)) {
          _set_bit(new_bs, i);
       }
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#xor(other) ⇒ Object Also known as: ^, symmetric_difference 



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# File 'ext/bitset/bitset.c', line 253

static VALUE rb_bitset_xor(VALUE self, VALUE other) {
    Bitset * bs = get_bitset(self);
    Bitset * other_bs = get_bitset(other);
    Bitset * new_bs;
    int max = INTS(bs);
    int i;

    verify_equal_size(bs, other_bs);
    new_bs = bitset_new();
    bitset_setup(new_bs, bs->len);

    for(i = 0; i < max; i++) {
        uint64_t segment = bs->data[i];
        uint64_t other_segment = other_bs->data[i];
        new_bs->data[i] = segment ^ other_segment;
    }

    return Data_Wrap_Struct(cBitset, 0, bitset_free, new_bs);
}

#xor!(other) ⇒ Object Also known as: symmetric_difference! 



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# File 'ext/bitset/bitset.c', line 571

static VALUE rb_bitset_xor_mutable(VALUE self, VALUE other) {
    return mutable(self, other, &xor);
}