tf.compat.v1.InteractiveSession

A TensorFlow Session for use in interactive contexts, such as a shell.

Used in the notebooks

Used in the tutorials

The only difference with a regular Session is that an InteractiveSession installs itself as the default session on construction. The methods tf.Tensor.eval and tf.Operation.run will use that session to run ops.

This is convenient in interactive shells and IPython notebooks, as it avoids having to pass an explicit Session object to run ops.

For example:

sess = tf.compat.v1.InteractiveSession()
a = tf.constant(5.0)
b = tf.constant(6.0)
c = a * b
# We can just use 'c.eval()' without passing 'sess'
print(c.eval())
sess.close()

Note that a regular session installs itself as the default session when it is created in a with statement. The common usage in non-interactive programs is to follow that pattern:

a = tf.constant(5.0)
b = tf.constant(6.0)
c = a * b
with tf.compat.v1.Session():
  # We can also use 'c.eval()' here.
  print(c.eval())

target (Optional.) The execution engine to connect to. Defaults to using an in-process engine.
graph (Optional.) The Graph to be launched (described above).
config (Optional) ConfigProto proto used to configure the session.

graph The graph that was launched in this session.
graph_def A serializable version of the underlying TensorFlow graph.
sess_str The TensorFlow process to which this session will connect.

Methods

as_default

View source

Returns a context manager that makes this object the default session.

Use with the with keyword to specify that calls to tf.Operation.run or tf.Tensor.eval should be executed in this session.

c = tf.constant(..)
sess = tf.compat.v1.Session()

with sess.as_default():
  assert tf.compat.v1.get_default_session() is sess
  print(c.eval())

To get the current default session, use tf.compat.v1.get_default_session.

c = tf.constant(...)
sess = tf.compat.v1.Session()
with sess.as_default():
  print(c.eval())
# ...
with sess.as_default():
  print(c.eval())

sess.close()

Alternatively, you can use with tf.compat.v1.Session(): to create a session that is automatically closed on exiting the context, including when an uncaught exception is raised.

Returns
A context manager using this session as the default session.

close

View source

Closes an InteractiveSession.

list_devices

View source

Lists available devices in this session.

devices = sess.list_devices()
for d in devices:
  print(d.name)

Where:

Each element in the list has the following properties

  • name: A string with the full name of the device. ex: /job:worker/replica:0/task:3/device:CPU:0
  • device_type: The type of the device (e.g. CPU, GPU, TPU.)
  • memory_limit: The maximum amount of memory available on the device. Note: depending on the device, it is possible the usable memory could be substantially less.

Raises
tf.errors.OpError If it encounters an error (e.g. session is in an invalid state, or network errors occur).

Returns
A list of devices in the session.

make_callable

View source

Returns a Python callable that runs a particular step.

The returned callable will take len(feed_list) arguments whose types must be compatible feed values for the respective elements of feed_list. For example, if element i of feed_list is a tf.Tensor, the ith argument to the returned callable must be a numpy ndarray (or something convertible to an ndarray) with matching element type and shape. See tf.Session.run for details of the allowable feed key and value types.

The returned callable will have the same return type as tf.Session.run(fetches, ...). For example, if fetches is a tf.Tensor, the callable will return a numpy ndarray; if fetches is a tf.Operation, it will return None.

Args
fetches A value or list of values to fetch. See tf.Session.run for details of the allowable fetch types.
feed_list (Optional.) A list of feed_dict keys. S