The Session graph is empty. Add operations to the graph before calling run().

这个问题通常出现在 TensorFlow 的 Session 中，意味着你在运行 Session.run() 之前没有在图中添加任何操作。你需要在 Session 中创建一个图并添加一些操作，例如：

import tensorflow as tf

# 创建一个图
graph = tf.Graph()

with graph.as_default():
    # 添加一些操作
    a = tf.constant(5)
    b = tf.constant(10)
    c = tf.add(a, b)

# 创建一个会话并运行操作
with tf.Session(graph=graph) as sess:
    result = sess.run(c)
    print(result)

在这个例子中，我们创建了一个图并添加了三个操作：常量 a 和 b，以及将它们加起来的操作 c。然后我们用这个图创建了一个会话并运行了操作 c，得到了正确的结果 15。

相关问题

failed to execute tez graph.java.lang.IndexOutOfBoundsException

这个错误信息包含了两个不同的问题。第一个问题是java.lang.IndexOutOfBoundsException，它表示数组或集合的索引越界。第二个问题是Failed to execute tez graph，它表示在执行tez图时出现了错误。这两个问题可能是相关的，也可能是独立的问题。要解决这些问题，可以尝试以下方法：
1. 对于java.lang.IndexOutOfBoundsException，可以检查代码中是否有数组或集合的索引越界。如果有，需要修复代码以确保不会出现这种情况。
2. 对于Failed to execute tez graph，可以检查tez的配置是否正确，并确保所有必需的文件和库都已正确安装。还可以尝试重新启动tez服务或重新安装tez。
3. 如果以上方法都无法解决问题，可以尝试查找类似的错误信息并查看其他人是如何解决的。可以在网上搜索相关的解决方案或者咨询相关的技术支持人员。

Write a program with the following requirements: 1. Use a 5x5 boolean two-dimensional array to represent the connectivity of the graphs that need to be traversed. 2. Use depth first algorithm to traverse the graph. 3. Use breadth first algorithm to traverse the graph. 4. The starting position of the traversal is chosen reasonably based on the connectivity of the graph.

Alright, I understand your requirements. Here's a Python program that satisfies your specifications:

import queue

# Define the 5x5 boolean two-dimensional array to represent the connectivity of the graphs
graph = [
  [False, True, False, True, False],
  [True, False, True, False, True],
  [False, True, False, True, False],
  [True, False, True, False, True],
  [False, True, False, True, False],
]

# Define the depth first traversal function
def depth_first_traversal(graph, start):
  visited = [False] * len(graph)
  stack = [start]

  while stack:
    vertex = stack.pop()
    if not visited[vertex]:
      print(vertex, end=" ")
      visited[vertex] = True
      for i in range(len(graph)):
        if graph[vertex][i] and not visited[i]:
          stack.append(i)

# Define the breadth first traversal function
def breadth_first_traversal(graph, start):
  visited = [False] * len(graph)
  q = queue.Queue()
  q.put(start)

  while not q.empty():
    vertex = q.get()
    if not visited[vertex]:
      print(vertex, end=" ")
      visited[vertex] = True
      for i in range(len(graph)):
        if graph[vertex][i] and not visited[i]:
          q.put(i)

# Choose a reasonable starting position for the traversal based on the connectivity of the graph
start = 0
for i in range(len(graph)):
  if sum(graph[i]) > sum(graph[start]):
    start = i

# Perform depth first traversal
print("Depth First Traversal:")
depth_first_traversal(graph, start)

# Perform breadth first traversal
print("\nBreadth First Traversal:")
breadth_first_traversal(graph, start)

In this program, we first define the 5x5 boolean two-dimensional array `graph` to represent the connectivity of the graphs that need to be traversed. Then, we define the `depth_first_traversal` function and the `breadth_first_traversal` function to perform depth first and breadth first traversal of the graph respectively.

Next, we choose a reasonable starting position for the traversal based on the connectivity of the graph. We do this by iterating over each vertex in the graph and comparing the number of its neighbors to the number of neighbors of the current starting vertex. We choose the vertex with the highest number of neighbors as the starting position.

Finally, we call the `depth_first_traversal` function and the `breadth_first_traversal` function with the `graph` and `start` arguments to perform the traversals. The output of the program will be the sequence of vertices visited during the traversals.