From ac5febb1a24d7a5efa797b178dcdbfb4b5462d69 Mon Sep 17 00:00:00 2001
From: Leonid Boytsov <leo@Leonids-MacBook-Pro.local>
Date: Wed, 25 Jul 2018 22:28:42 -0400
Subject: [PATCH] Testing script for #337

---
 python_bindings/notebooks/test_hnsw_recall.py | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100755 python_bindings/notebooks/test_hnsw_recall.py

diff --git a/python_bindings/notebooks/test_hnsw_recall.py b/python_bindings/notebooks/test_hnsw_recall.py
new file mode 100755
index 0000000..96534ba
--- /dev/null
+++ b/python_bindings/notebooks/test_hnsw_recall.py
@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+import logging
+# Uncomment to print logs to the screen
+#logging.basicConfig(level=logging.INFO)
+
+import numpy as np
+import sys 
+import nmslib 
+import time 
+import math 
+from sklearn.neighbors import NearestNeighbors
+
+
+def testHnswRecallL2(dataMatrix, queryMatrix, k, M=30, efC=200, efS=1000, numThreads=4):
+  queryQty = queryMatrix.shape[0]
+  indexTimeParams = {'M': M, 'indexThreadQty': numThreads, 'efConstruction': efC, 'post' : 0}
+
+  #Indexing
+  print('Index-time parameters', indexTimeParams)
+  spaceName='l2'
+  index = nmslib.init(method='hnsw', space=spaceName, data_type=nmslib.DataType.DENSE_VECTOR) 
+  index.addDataPointBatch(dataMatrix)  
+
+  start = time.time()
+  index.createIndex(indexTimeParams) 
+  end = time.time() 
+  print('Indexing time = %f' % (end-start))
+
+
+  # Querying
+  start = time.time()
+  nmslibFound = index.knnQueryBatch(queryMatrix, k=k, num_threads=numThreads)
+  end = time.time()
+  print('kNN time total=%f (sec), per query=%f (sec), per query adjusted for thread number=%f (sec)' %
+        (end - start, float(end - start) / queryQty, numThreads * float(end - start) / queryQty))
+
+
+  # Computing gold-standard data 
+  print('Computing gold-standard data')
+
+  start = time.time()
+  sindx = NearestNeighbors(n_neighbors=k, metric='l2', algorithm='brute').fit(dataMatrix)
+  end = time.time()
+
+  print('Brute-force preparation time %f' % (end - start))
+
+  start = time.time() 
+  bruteForceFound = sindx.kneighbors(queryMatrix)
+  end = time.time()
+
+  print('brute-force kNN time total=%f (sec), per query=%f (sec)' % 
+       (end-start, float(end-start)/queryQty) )
+
+  # Setting query-time parameters
+  queryTimeParams = {'efSearch': efS}
+  print('Setting query-time parameters', queryTimeParams)
+  index.setQueryTimeParams(queryTimeParams)
+
+  # Finally computing recall for every i-th neighbor
+  for n in range(k):
+    recall=0.0
+    for i in range(0, queryQty):
+      correctSet = set(bruteForceFound[1][i])
+      retArr = nmslibFound[i][0]
+      retElem = retArr[n] if len(retArr) > n else -1
+
+      recall = recall + int(retElem in correctSet)
+    recall = recall / queryQty
+    print('kNN recall for neighbor %d %f' % (n+1, recall))
+
+
+def testRandom(dataQty, queryQty, efS, dim, k):
+  queryQty = min(dataQty, queryQty)
+  dataMatrix = np.random.randn(dataQty, dim).astype(np.float32)
+  indx = np.random.choice(np.arange(dataQty), size=queryQty, replace=False)
+  queryMatrix = dataMatrix[indx, ].astype(np.float32)
+  testHnswRecallL2(dataMatrix, queryMatrix, k, efS=efS)
+
+testRandom(100_000, 10, dim=100, k=10, efS=1000)
+  
+