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I'm not sure what line width Pari used, but it wasn't 80 columns.

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This will probably make the merge of #663 and other LSH improvements by Yannis
harder...
This commit is contained in:
Ryan Curtin
2016-05-31 16:56:11 -04:00
parent 02e31b3b07
commit e6d2ca7bf6
1 changed files with 17 additions and 17 deletions
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src/mlpack/methods/lsh/lsh_search_impl.hpp
+17 -17
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@@ -358,19 +358,19 @@ template<typename SortPolicy>
void LSHSearch<SortPolicy>::BuildHash()
{
// The first level hash for a single table outputs a 'numProj'-dimensional
// integer key for each point in the set -- (key, pointID)
// The key creation details are presented below
// integer key for each point in the set -- (key, pointID). The key creation
// details are presented below.
//
// The second level hash is performed by hashing the key to
// an integer in the range [0, 'secondHashSize').
// The second level hash is performed by hashing the key to an integer in the
// range [0, 'secondHashSize').
//
// This is done by creating a weight vector 'secondHashWeights' of
// length 'numProj' with each entry an integer randomly chosen
// between [0, 'secondHashSize').
// This is done by creating a weight vector 'secondHashWeights' of length
// 'numProj' with each entry an integer randomly chosen between [0,
// 'secondHashSize').
//
// Then the bucket for any key and its corresponding point is
// given by <key, 'secondHashWeights'> % 'secondHashSize'
// and the corresponding point ID is put into that bucket.
// Then the bucket for any key and its corresponding point is given by <key,
// 'secondHashWeights'> % 'secondHashSize' and the corresponding point ID is
// put into that bucket.
// Step I: Prepare the second level hash.
@@ -379,9 +379,9 @@ void LSHSearch<SortPolicy>::BuildHash()
(double) secondHashSize);
// The 'secondHashTable' is initially an empty matrix of size
// ('secondHashSize' x 'bucketSize'). But by only filling the buckets
// as points land in them allows us to shrink the size of the
// 'secondHashTable' at the end of the hashing.
// ('secondHashSize' x 'bucketSize'). But by only filling the buckets as
// points land in them allows us to shrink the size of the 'secondHashTable'
// at the end of the hashing.
// Fill the second hash table n = referenceSet.n_cols. This is because no
// point has index 'n' so the presence of this in the bucket denotes that
@@ -404,8 +404,8 @@ void LSHSearch<SortPolicy>::BuildHash()
size_t numRowsInTable = 0;
// Step II: The offsets for all projections in all tables.
// Since the 'offsets' are in [0, hashWidth], we obtain the 'offsets'
// as randu(numProj, numTables) * hashWidth.
// Since the 'offsets' are in [0, hashWidth], we obtain the 'offsets' as
// randu(numProj, numTables) * hashWidth.
offsets.randu(numProj, numTables);
offsets *= hashWidth;
@@ -416,8 +416,8 @@ void LSHSearch<SortPolicy>::BuildHash()
{
// Step IV: Obtain the 'numProj' projections for each table.
// For L2 metric, 2-stable distributions are used, and
// the normal Z ~ N(0, 1) is a 2-stable distribution.
// For L2 metric, 2-stable distributions are used, and the normal Z ~ N(0,
// 1) is a 2-stable distribution.
arma::mat projMat;
projMat.randn(referenceSet->n_rows, numProj);