Added RMR

Author: gourav3017

compress_rtp/utils/get_sparse_only.py

@@ -0,0 +1,30 @@
+import numpy as np
+import math
+import scipy
+
+
+def get_sparse_only(matrix, threshold_perc, compression='naive'):
+    threshold = np.max(matrix) * threshold_perc*0.01
+    if compression == 'rmr':
+        copy_matrix = matrix.copy()
+        print('Generating sparse matrix using RMR...')
+        np.apply_along_axis(row_operation, 1, copy_matrix, threshold)
+        S = scipy.sparse.csr_matrix(copy_matrix)
+    else:
+        S = np.where(matrix >= threshold, matrix, 0)
+        S = scipy.sparse.csr_matrix(S)
+    return S
+
+
+def row_operation(copy_row, threshold):
+    argzero = np.argwhere((np.abs(copy_row) <= threshold) * (copy_row != 0))
+    argzero = argzero.reshape(len(argzero), )
+    argzero_copy = copy_row[argzero]
+    copy_row[argzero] = 0
+    sum = np.sum(argzero_copy)
+    if sum != 0:
+        k = math.ceil(sum / threshold)
+
+        indices = np.random.choice(argzero, k, p=argzero_copy / sum, replace=True)
+        np.add.at(copy_row, indices, sum / k)
+