add getData method

Author: lanking520

scala-package/core/src/main/scala/org/apache/mxnet/LibInfo.scala

@@ -123,6 +123,7 @@ private[mxnet] class LibInfo {
   @native def mxNDArraySave(fname: String,
                             handles: Array[NDArrayHandle],
                             keys: Array[String]): Int
+  @native def mxNDArrayGetDataNDArray(handle: NDArrayHandle, out: NDArrayHandleRef): Int
   @native def mxNDArrayGetAuxNDArray(handle: NDArrayHandle,
                                      location: Int,
                                      out: NDArrayHandleRef): Int

scala-package/core/src/main/scala/org/apache/mxnet/SparseNDArray.scala

@@ -151,6 +151,19 @@ class SparseNDArray private[mxnet] (override private[mxnet] val handle: NDArrayH
     dense.at(idx)
   }
 
+  /**
+    * Get the Data portion from the row Sparse NDArray
+    * @return NDArray
+    */
+  def getData: NDArray = {
+    val handle = new NDArrayHandleRef
+    if (this.sparseFormat == SparseFormat.CSR) {
+      throw new UnsupportedOperationException("Not Supported for CSR")
+    }
+    _LIB.mxNDArrayGetDataNDArray(this.handle, handle)
+    new NDArray(handle.value, false)
+  }
+
   /**
     * Get the indptr Array
     * @return NDArray

scala-package/core/src/test/scala/org/apache/mxnet/SparseNDArraySuite.scala

@@ -65,7 +65,7 @@ class SparseNDArraySuite  extends FunSuite {
     printf(rspIn.toString)
     val toRetain = Array(0f, 3f)
     val rspOut = SparseNDArray.retain(rspIn, toRetain)
-    assert(rspOut.at(0).toArray sameElements Array(1f, 2f))
+    assert(rspOut.getData.toArray sameElements Array(1f, 2f, 5f, 6f))
     assert(rspOut.getIndices.toArray sameElements Array(0f, 3f))
   }
 

scala-package/native/src/main/native/org_apache_mxnet_native_c_api.cc

@@ -474,6 +474,15 @@ JNIEXPORT jint JNICALL Java_org_apache_mxnet_LibInfo_mxFloat64NDArraySyncCopyFro
   return ret;
 }
 
+JNIEXPORT jint JNICALL Java_org_apache_mxnet_LibInfo_mxNDArrayGetDataNDArray
+  (JNIEnv *env, jobject obj, jlong arrayPtr, jobject ndArrayHandle) {
+  NDArrayHandle out;
+  int ret = MXNDArrayGetDataNDArray(reinterpret_cast<NDArrayHandle>(arrayPtr),
+                                     &out);
+  SetLongField(env, ndArrayHandle, reinterpret_cast<jlong>(out));
+  return ret;
+}
+
 JNIEXPORT jint JNICALL Java_org_apache_mxnet_LibInfo_mxNDArrayGetAuxNDArray
   (JNIEnv *env, jobject obj, jlong arrayPtr, jint location, jobject ndArrayHandle) {
   NDArrayHandle out;