Merge pull request #2636 from jacquesqiao/fix-converter

fix dim problem

doc/getstarted/concepts/use_concepts_cn.rst

@@ -111,7 +111,7 @@ PaddlePaddle支持不同类型的输入数据，主要包括四种类型，和
     # define training dataset reader
     def train_reader():
         train_x = np.array([[1, 1], [1, 2], [3, 4], [5, 2]])
-        train_y = np.array([-2, -3, -7, -7])
+        train_y = np.array([[-2], [-3], [-7], [-7]])
         def reader():
             for i in xrange(train_y.shape[0]):
                 yield train_x[i], train_y[i]

paddle/py_paddle/dataprovider_converter.py

@@ -109,6 +109,10 @@ class DenseScanner(IScanner):
             if len(self.__shape__) > 3:
                 raise ValueError(
                     "The dimension of input cannot be greater than 3.")
+            if len(self.__shape__) == 0:
+                raise ValueError(
+                    "The input should be a vector, please check your input data."
+                )
             self.__dim__ = reduce(lambda x, y: x * y, self.__shape__)
             if len(self.__shape__) == 1 and self.__dim__ != self.input_type.dim:
                 raise ValueError(