Moved create_random_projection_hash() into its own file.

dlib/lsh.h

@@ -5,6 +5,7 @@
 
 
 #include "lsh/projection_hash.h"
+#include "lsh/create_random_projection_hash.h"
 
 
 #endif // DLIB_LSh_

dlib/lsh/create_random_projection_hash.h

+// Copyright (C) 2011  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+#ifndef DLIB_CREATE_RANDOM_PROJECTION_HAsH_H__
+#define DLIB_CREATE_RANDOM_PROJECTION_HAsH_H__
+
+#include "create_random_projection_hash_abstract.h"
+#include "projection_hash.h"
+#include "../matrix.h"
+#include "../rand.h"
+#include <vector>
+
+namespace dlib
+{
+
+// ----------------------------------------------------------------------------------------
+
+    template <typename vector_type>
+    projection_hash create_random_projection_hash (
+        const vector_type& v,
+        const int bits
+    ) 
+    {
+
+        // compute a whitening matrix
+        matrix<double> whiten = trans(chol(pinv(covariance(vector_to_matrix(v)))));
+
+
+        // hashes
+        std::vector<unsigned long> h(v.size(),0);
+
+        std::vector<double> vals(v.size(),0);
+
+        // number of hits for each hash value
+        std::vector<unsigned long> counts;
+
+        std::vector<double> temp;
+
+        // build a random projection matrix
+        dlib::rand rnd;
+        matrix<double> proj(bits, v[0].size());
+        for (long r = 0; r < proj.nr(); ++r)
+            for (long c = 0; c < proj.nc(); ++c)
+                proj(r,c) = rnd.get_random_gaussian();
+
+        // merge whitening matrix with projection matrix
+        proj = proj*whiten;
+
+        matrix<double,0,1> offset(bits);
+
+
+        // figure out what the offset values should be
+        for (int itr = 0; itr < offset.size(); ++itr)
+        {
+            counts.assign(std::pow(2,bits), 0);
+            // count the popularity of each hash value
+            for (unsigned long i = 0; i < h.size(); ++i)
+            {
+                h[i] <<= 1;
+                counts[h[i]] += 1;
+            }
+
+            const unsigned long max_h = index_of_max(vector_to_matrix(counts));
+
+            temp.clear();
+            for (unsigned long i = 0; i < v.size(); ++i)
+            {
+                vals[i] = dot(rowm(proj,itr), v[i]);
+                if (h[i] == max_h)
+                    temp.push_back(vals[i]);
+            }
+
+            // split down the middle
+            std::sort(temp.begin(), temp.end());
+            const double split = temp[temp.size()/2];
+            offset(itr) = -split;
+
+            for (unsigned long i = 0; i < vals.size(); ++i)
+            {
+                if (vals[i] - split > 0)
+                    h[i] |= 1;
+            }
+        }
+
+
+        return projection_hash(proj, offset);
+    }
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_CREATE_RANDOM_PROJECTION_HAsH_H__
+

dlib/lsh/create_random_projection_hash_abstract.h

+// Copyright (C) 2011  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+#undef DLIB_CREATE_RANDOM_PROJECTION_HAsH_ABSTRACT_H__
+#ifdef DLIB_CREATE_RANDOM_PROJECTION_HAsH_ABSTRACT_H__
+
+#include "projection_hash_abstract.h"
+#include "../rand.h"
+
+namespace dlib
+{
+
+// ----------------------------------------------------------------------------------------
+
+    template <typename vector_type>
+    projection_hash create_random_projection_hash (
+        const vector_type& v,
+        const int bits
+    );
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_CREATE_RANDOM_PROJECTION_HAsH_ABSTRACT_H__
+
+

dlib/lsh/projection_hash.h

@@ -89,79 +89,6 @@ namespace dlib
         item = projection_hash(proj, offset);
     }
 
-// ----------------------------------------------------------------------------------------
-
-    template <typename vector_type>
-    projection_hash create_random_projection_hash (
-        const vector_type& v,
-        const int bits
-    ) 
-    {
-
-        // compute a whitening matrix
-        matrix<double> whiten = trans(chol(pinv(covariance(vector_to_matrix(v)))));
-
-
-        // hashes
-        std::vector<unsigned long> h(v.size(),0);
-
-        std::vector<double> vals(v.size(),0);
-
-        // number of hits for each hash value
-        std::vector<unsigned long> counts;
-
-        std::vector<double> temp;
-
-        // build a random projection matrix
-        dlib::rand rnd;
-        matrix<double> proj(bits, v[0].size());
-        for (long r = 0; r < proj.nr(); ++r)
-            for (long c = 0; c < proj.nc(); ++c)
-                proj(r,c) = rnd.get_random_gaussian();
-
-        // merge whitening matrix with projection matrix
-        proj = proj*whiten;
-
-        matrix<double,0,1> offset(bits);
-
-
-        // figure out what the offset values should be
-        for (int itr = 0; itr < offset.size(); ++itr)
-        {
-            counts.assign(std::pow(2,bits), 0);
-            // count the popularity of each hash value
-            for (unsigned long i = 0; i < h.size(); ++i)
-            {
-                h[i] <<= 1;
-                counts[h[i]] += 1;
-            }
-
-            const unsigned long max_h = index_of_max(vector_to_matrix(counts));
-
-            temp.clear();
-            for (unsigned long i = 0; i < v.size(); ++i)
-            {
-                vals[i] = dot(rowm(proj,itr), v[i]);
-                if (h[i] == max_h)
-                    temp.push_back(vals[i]);
-            }
-
-            // split down the middle
-            std::sort(temp.begin(), temp.end());
-            const double split = temp[temp.size()/2];
-            offset(itr) = -split;
-
-            for (unsigned long i = 0; i < vals.size(); ++i)
-            {
-                if (vals[i] - split > 0)
-                    h[i] |= 1;
-            }
-        }
-
-
-        return projection_hash(proj, offset);
-    }
-
 // ----------------------------------------------------------------------------------------
 
 }

dlib/lsh/projection_hash_abstract.h

@@ -4,8 +4,6 @@
 #ifdef DLIB_PROJECTION_HASh_ABSTRACT_H__
 
 #include "../matrix.h"
-#include "../rand.h"
-#include <vector>
 
 namespace dlib
 {
@@ -55,14 +53,6 @@ namespace dlib
         std::istream& in 
     );
 
-// ----------------------------------------------------------------------------------------
-
-    template <typename vector_type>
-    projection_hash create_random_projection_hash (
-        const vector_type& v,
-        const int bits
-    );
-
 // ----------------------------------------------------------------------------------------
 
 }