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Fix typing for bit array representation

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For now we keep the bit array representation code
around in case someone has bloom filters
persisted that use this representation. Going
forward we should remove this from the code.
This commit is contained in:
Kresten Krab Thorup 2012-09-26 15:27:56 +02:00
parent c439b510f9
commit 923dbe3852
1 changed files with 13 additions and 4 deletions
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17
src/hanoidb_bloom.erl
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@ -41,12 +41,14 @@
-define(W, 27). -define(W, 27).
-type bitmask() :: array() | any().
-record(bloom, { -record(bloom, {
e :: float(), % error probability e :: float(), % error probability
n :: non_neg_integer(), % maximum number of elements n :: non_neg_integer(), % maximum number of elements
mb :: non_neg_integer(), % 2^mb = m, the size of each slice (bitvector) mb :: non_neg_integer(), % 2^mb = m, the size of each slice (bitvector)
size :: non_neg_integer(), % number of elements size :: non_neg_integer(), % number of elements
a :: [array()] % list of bitvectors a :: [bitmask()] % list of bitvectors
}). }).
-record(sbf, { -record(sbf, {
@ -195,7 +197,7 @@ bitmask_new(LogN) ->
bitmask_set(I, BM) -> bitmask_set(I, BM) ->
case element(1,BM) of case element(1,BM) of
array -> bitarray_set(I, BM); array -> bitarray_set(I, as_array(BM));
sparse_bitmap -> hanoidb_sparse_bitmap:set(I, BM); sparse_bitmap -> hanoidb_sparse_bitmap:set(I, BM);
dense_bitmap_ets -> hanoidb_dense_bitmap:set(I, BM); dense_bitmap_ets -> hanoidb_dense_bitmap:set(I, BM);
dense_bitmap -> dense_bitmap ->
@ -213,17 +215,24 @@ bitmask_build(BM) ->
bitmask_get(I, BM) -> bitmask_get(I, BM) ->
case element(1,BM) of case element(1,BM) of
array -> bitarray_get(I, BM); array -> bitarray_get(I, as_array(BM));
sparse_bitmap -> hanoidb_sparse_bitmap:member(I, BM); sparse_bitmap -> hanoidb_sparse_bitmap:member(I, BM);
dense_bitmap_ets -> hanoidb_dense_bitmap:member(I, BM); dense_bitmap_ets -> hanoidb_dense_bitmap:member(I, BM);
dense_bitmap -> hanoidb_dense_bitmap:member(I, BM) dense_bitmap -> hanoidb_dense_bitmap:member(I, BM)
end. end.
-spec as_array(bitmask()) -> array().
as_array(BM) ->
case array:is_array(BM) of
true -> BM
end.
%%%========== Bitarray representation - suitable for sparse arrays ========== %%%========== Bitarray representation - suitable for sparse arrays ==========
bitarray_new(N) -> array:new((N-1) div ?W + 1, {default, 0}). bitarray_new(N) -> array:new((N-1) div ?W + 1, {default, 0}).
-spec bitarray_set( non_neg_integer(), array() ) -> array(). -spec bitarray_set( non_neg_integer(), array() ) -> array().
bitarray_set(I, A) -> bitarray_set(I, A1) ->
A = as_array(A1),
AI = I div ?W, AI = I div ?W,
V = array:get(AI, A), V = array:get(AI, A),
V1 = V bor (1 bsl (I rem ?W)), V1 = V bor (1 bsl (I rem ?W)),