Class: Containers::Bitset

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

Overview

Copyright © 2011 Tyler McMullen

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ary) ⇒ Object 


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# File 'ext/containers/bitset/bitset.c', line 59

static VALUE rb_bitset_initialize(VALUE self, VALUE ary) {
    Bitset * bs = get_bitset(self);
    if (RB_TYPE_P(ary, T_ARRAY)) {
        int i;
        int len = (int) RARRAY_LEN(ary);
        bitset_setup(bs, len);
        for (i = 0; i < len; ++i) {
            // This could be more efficient, but if you're converting
            // from a Ruby array of bits, you're not looking
            // at blazing speed anyhow.
            if (RTEST(rb_ary_entry(ary, i))) {
                _set_bit(bs, i);
            }
        }
    } else {
        bitset_setup(bs, NUM2INT(ary));
    }
    return self;
}

Class Method Details

.from_s(s) ⇒ Object 


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

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/containers/bitset.rb', line 42

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/containers/bitset/bitset.c', line 569

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/containers/bitset/bitset.c', line 107

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/containers/bitset/bitset.c', line 114

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/containers/bitset/bitset.c', line 232

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/containers/bitset/bitset.c', line 174

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/containers/bitset/bitset.c', line 196

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/containers/bitset/bitset.c', line 277

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/containers/bitset/bitset.c', line 619

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/containers/bitset/bitset.c', line 428

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/containers/bitset/bitset.c', line 380

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/containers/bitset/bitset.c', line 441

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/containers/bitset/bitset.c', line 521

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;
}

#flip(*args) ⇒ Object 


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# File 'ext/containers/bitset/bitset.c', line 144

static VALUE rb_bitset_flip(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);
            if (_get_bit(bs, idx) == 0) {
                _set_bit(bs, idx);
            } else {
                _clear_bit(bs, idx);
            }
        }
    } else {
        for(i = 0; i < argc; i++) {
            VALUE index = argv[i];
            int idx = NUM2INT(index);
            validate_index(bs, idx);
            if (_get_bit(bs, idx) == 0) {
                _set_bit(bs, idx);
            } else {
                _clear_bit(bs, idx);
            }
        }
    }
    return Qtrue;
}

#hamming(other) ⇒ Object 


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# File 'ext/containers/bitset/bitset.c', line 364

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/containers/bitset/bitset.c', line 237

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/containers/bitset/bitset.c', line 611

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

#marshal_dump ⇒ Object 


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# File 'ext/containers/bitset/bitset.c', line 391

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/containers/bitset/bitset.c', line 402

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/containers/bitset/bitset.c', line 317

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/containers/bitset.rb', line 34

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/containers/bitset/bitset.c', line 623

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/containers/bitset/bitset.c', line 554

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/containers/bitset/bitset.c', line 122

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/containers/bitset/bitset.c', line 209

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 ⇒ Object Also known as: length 


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# File 'ext/containers/bitset/bitset.c', line 79

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

#to_binary_array ⇒ Object 


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# File 'ext/containers/bitset/bitset.c', line 416

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 Also known as: inspect 


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# File 'ext/containers/bitset/bitset.c', line 334

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/containers/bitset/bitset.c', line 257

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/containers/bitset/bitset.c', line 607

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/containers/bitset/bitset.c', line 535

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/containers/bitset/bitset.c', line 297

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/containers/bitset/bitset.c', line 615

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