创建dataset的方法

1，几种方法

Create a source dataset using one of the factory functions like Dataset.from_tensors, Dataset.from_tensor_slices or using objects that read from files like TextLineDataset or TFRecordDataset

2，自数组

ds_tensors = tf.data.Dataset.from_tensor_slices([1, 2, 3, 4, 5, 6])

3，自文件

# Create a CSV file
import tempfile
_, filename = tempfile.mkstemp()

with open(filename, 'w') as f:
f.write("""Line 1
Line 2
Line 3
""")

ds_file = tf.data.TextLineDataset(filename)