Simplify calc in test_sequence_erase_op

paddle/operators/sequence_erase_op.cc

@@ -50,7 +50,7 @@ class SequenceEraseOpMaker : public framework::OpProtoAndCheckerMaker {
     AddComment(R"DOC(
 Sequence Erase Operator.
 
-Sequence erase operator erases tokens specified by Attr(tokens) in the input 
+Sequence erase operator erases tokens specified by Attr(tokens) from the input 
 sequences Input(X), and outputs the remaining data and modifies the LoD 
 information at the same time. For example, given a 2-D LoDTensor
 

paddle/operators/sequence_erase_op.cu

@@ -70,6 +70,8 @@ class SequenceEraseOpCUDAKernel : public framework::OpKernel<T> {
 
     auto lod = in->lod();
     PADDLE_ENFORCE_EQ(lod.size(), 1UL, "Only support one level sequence now.");
+    PADDLE_ENFORCE_EQ(lod[0].back(), (size_t)in->numel(),
+                      "The actual size mismatches with the LoD information.");
     auto tokens = ctx.Attr<std::vector<T>>("tokens");
     auto tokens_len = tokens.size();
     auto in_len = in->numel();

paddle/operators/sequence_erase_op.h

@@ -28,22 +28,27 @@ class SequenceEraseKernel : public framework::OpKernel<T> {
 
     auto lod = in->lod();
     PADDLE_ENFORCE_EQ(lod.size(), 1UL, "Only support one level sequence now.");
+    PADDLE_ENFORCE_EQ(lod[0].back(), (size_t)in->numel(),
+                      "The actual size mismatches with the LoD information.");
     auto tokens = ctx.Attr<std::vector<int>>("tokens");
     auto in_len = in->numel();
     auto in_dat = in->data<T>();
     auto lod0 = lod[0];
+
     std::vector<size_t> num_erased(in_len + 1, 0);
-    for (int64_t i = 1; i < in_len + 1; ++i) {
-      num_erased[i] = num_erased[i - 1];
-      if (std::find(tokens.begin(), tokens.end(), in_dat[i - 1]) !=
+    std::vector<size_t> out_lod0(1, 0);
+    for (size_t i = 0; i < lod0.size() - 1; ++i) {
+      size_t num_out = 0;
+      for (auto j = lod0[i] + 1; j <= lod0[i + 1]; ++j) {
+        num_erased[j] = num_erased[j - 1];
+        if (std::find(tokens.begin(), tokens.end(), in_dat[j - 1]) !=
             tokens.end()) {
-        num_erased[i] += 1;
+          num_erased[j] += 1;
+        } else {
+          num_out += 1;
         }
       }
-
-    std::vector<size_t> out_lod0(lod0.size(), 0);
-    for (size_t i = 1; i < lod0.size(); ++i) {
-      out_lod0[i] = lod0[i] - num_erased[lod0[i]];
+      out_lod0.push_back(out_lod0.back() + num_out);
     }
 
     auto out_len = in_len - num_erased[in_len];

python/paddle/v2/fluid/tests/test_sequence_erase_op.py

@@ -4,32 +4,23 @@ from op_test import OpTest
 
 
 def sequence_erase(in_seq, lod0, tokens):
-    # num_erased[i]: the number of elments to be removed before #i elements
-    num_erased = [0] * (len(in_seq) + 1)
-    for i in range(1, len(in_seq) + 1):
-        num_erased[i] = num_erased[i - 1]
-        if in_seq[i - 1] in tokens:
-            num_erased[i] += 1
-
-    # recalculate lod information
-    new_lod0 = [0] * len(lod0)
-    for i in range(1, len(lod0)):
-        new_lod0[i] = lod0[i] - num_erased[lod0[i]]
-
-    out_seq = np.zeros(
-        (len(in_seq) - num_erased[len(in_seq)], 1)).astype("int32")
-    for i in range(0, len(in_seq)):
-        if num_erased[i] == num_erased[i + 1]:
-            out_seq[i - num_erased[i]] = in_seq[i]
-        # else in_seq[i] needs to be removed 
-    return out_seq, new_lod0
+    new_lod0 = [0]
+    out_seq = []
+    for i in range(0, len(lod0) - 1):
+        num_out = 0
+        for dat in in_seq[lod0[i]:lod0[i + 1]]:
+            if dat not in tokens:
+                out_seq.append(dat)
+                num_out += 1
+        new_lod0.append(new_lod0[-1] + num_out)
+    return np.array(out_seq).astype("int32"), new_lod0
 
 
 class TestSequenceEraseOp(OpTest):
     def setUp(self):
         self.op_type = "sequence_erase"
-        in_seq = np.random.randint(0, 10, (10, 1)).astype("int32")
-        lod = [[0, 3, 6, 10]]
+        in_seq = np.random.randint(0, 10, (30, 1)).astype("int32")
+        lod = [[0, 9, 13, 24, 30]]
         tokens = [2, 3, 5]
         out_seq, new_lod0 = sequence_erase(in_seq, lod[0], tokens)
         self.attrs = {'tokens': tokens}
@@ -41,17 +32,4 @@ class TestSequenceEraseOp(OpTest):
 
 
 if __name__ == '__main__':
-    """
-    in_seq = np.random.randint(0, 10, (30, 1)).astype("int32")
-    lod0 = [0, 5, 15, 30]
-    tokens = [2, 5]
-    out_seq, new_lod = sequence_erase(in_seq, lod0, tokens)
-    
-    print lod0, new_lod
-    print("compare")
-    for i in range(0,  len(lod0)-1):
-        print(np.transpose(in_seq[lod0[i] : lod0[i+1]]))
-        print(np.transpose(out_seq[new_lod[i] : new_lod[i+1]]))
-        print("\n")
-    """
     unittest.main()