add XLink

XLink.cpp

+/* NiuTrans.Tensor - an open-source tensor library
+ * Copyright (C) 2018, Natural Language Processing Lab, Northestern University.
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * some public functions are defined here
+ * $Created by: XIAO Tong (xiaotong@mail.neu.edu.cn) 2018-07-04
+ *
+ */
+
+#include <stdio.h>
+#include "XLink.h"
+
+namespace nts{ // namespace nts(NiuTrans.Tensor)
+    
+} // namespace nts(NiuTrans.Tensor)
+

XLink.h

+/* NiuTrans.Tensor - an open-source tensor library
+ * Copyright (C) 2018, Natural Language Processing Lab, Northestern University.
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * some public functions are defined here
+ * $Created by: XIAO Tong (xiaotong@mail.neu.edu.cn) 2018-07-04
+ *
+ */
+
+#include <stdio.h>
+#include "XGlobal.h"
+#include "XTensor.h"
+
+#ifndef __XLINK_H__
+#define __XLINK_H__
+
+namespace nts{ // namespace nts(NiuTrans.Tensor)
+
+/* cross reference */
+struct XTensor;
+
+/*
+This defines the link among tensors in networks. XLink can be
+cast as a hyperedge in a graph. when we compute on tensors, we actually create a
+network where nodes are tensors and edges the connections among them. Each connection is
+a hyperedge whose head is the output tensor and tails are input tensors. E.g,
+c = a + b
+represents a network with three nodes (a, b and c) and a hyperedge that links a and b (tails) to c (head).
+ 
+   + (=c)
+  / \
+ a   b
+ 
+for c, we have a incoming edge (a, b) -> c
+for a, we also have a edge c -> a in the reverse order (in a view of acyclic directed graphs)
+*/
+struct XLink
+{
+    /* head of the hyperedge */
+    XTensor * head;
+    
+    /* tails of the hyperedge ∂*/
+    XTensor * tails[];
+    
+    XLink(){};
+    
+    ~XLink(){};
+};
+    
+} // namespace nts(NiuTrans.Tensor)
+
+#endif // __XLINK_H__

source/XBLAS.h

@@ -12,7 +12,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License.
+ * limitations under the License.b
  */
 
 /*
@@ -206,4 +206,4 @@ extern void UnloadBLAS();
 
 } /* end of the nts (NiuTrans.Tensor) namespace */
 
-#endif
\ No newline at end of file
+#endif

source/XTensor.h

@@ -21,7 +21,7 @@
  *
  * $Created by: XIAO Tong (xiaotong@mail.neu.edu.cn) 2017-07-31
  * I'm working while most of the students are enjoying their holidays :(
- * $Update by: LI Yinqiao (li.yin.qiao.2012@hotmail.com) 2017-11-18 bug fixes
+ * $Updated by: LI Yinqiao (li.yin.qiao.2012@hotmail.com) 2017-11-18 bug fixes
  *
  */
 
@@ -36,10 +36,14 @@
 #include "XList.h"
 #include "XDataType.h"
 #include "XMem.h"
+#include "XLink.h"
 
 /* the nts (NiuTrans.Tensor) namespace */
 namespace nts{
 
+/* cross reference */
+struct XLink;
+
 /* define the maximum number of dimensions in a tensor */
 #define MAX_TENSOR_DIM_NUM 6
 #define USE_BATCHED_STRIDED_MAT_MUL
@@ -47,9 +51,7 @@ namespace nts{
 #define MIN_TENSOR_SPLIT_LIST_NUM 1024
 #define MIN_TENSOR_CAT_NUM 8
 
-/*
-computation flags
-*/
+/* computation flags */
 #define UNSAFE_BUT_FAST_MEM
 #define FAST_MATRIX
 
@@ -59,7 +61,6 @@ is the parent class of XMatrix.
 */
 struct XTensor
 {
-public:
     /* memory pool */
     XMem * mem;
 
@@ -129,11 +130,24 @@ public:
 
     /* indicates whether the tensor is initialized or not */
     bool isInit;
+    
+    /*
+    the link used to form networks. Note that when we compute on tensors, we actually create a
+    network where nodes are tensors and edges the connections among them. Each connection is
+    a hyperedge whose head is the output tensor and tails are input tensors. E.g,
+    c = a + b
+    represents a network with three nodes (a, b and c) and a hyperedge that links a and b (tails) to c (head).
+    Here "income" keeps which nodes (tensors) are used to form the current node (tensor).
+    */
+    XLink * income;
+    
+    /* It keeps which nodes (tensors) we go to from the current node (tensor). */
+    XLink * outgo;
 
-/*******************************************************************
-XTensor untilities
-*/
-public:
+    /********************
+     XTensor untilities
+    ********************/
+    
     /* constructor */
     XTensor();