tf.compat.v1.summary.scalar

Outputs a Summary protocol buffer containing a single scalar value.

tf.compat.v1.summary.scalar(
    name, tensor, collections=None, family=None
)

Migrate to TF2

Caution: This API was designed for TensorFlow v1. Continue reading for details on how to migrate from this API to a native TensorFlow v2 equivalent. See the TensorFlow v1 to TensorFlow v2 migration guide for instructions on how to migrate the rest of your code.

For compatibility purposes, when invoked in TF2 where the outermost context is eager mode, this API will check if there is a suitable TF2 summary writer context available, and if so will forward this call to that writer instead. A "suitable" writer context means that the writer is set as the default writer, and there is an associated non-empty value for step (see tf.summary.SummaryWriter.as_default, tf.summary.experimental.set_step or alternatively tf.compat.v1.train.create_global_step). For the forwarded call, the arguments here will be passed to the TF2 implementation of tf.summary.scalar, and the return value will be an empty bytestring tensor, to avoid duplicate summary writing. This forwarding is best-effort and not all arguments will be preserved.

To migrate to TF2, please use tf.summary.scalar instead. Please check Migrating tf.summary usage to TF 2.0 for concrete steps for migration. tf.summary.scalar can also log training metrics in Keras, you can check Logging training metrics in Keras for detials.

How to Map Arguments

TF1 Arg Name	TF2 Arg Name	Note
name	name	-
tensor	data	-
-	step	Explicit int64-castable monotonic step value. If omitted, this defaults to tf.summary.experimental.get_step().
collections	Not Supported	-
family	Removed	Please use tf.name_scope instead to manage summary name prefix.
-	description	Optional long-form str description for the summary. Markdown is supported. Defaults to empty.

Description

The generated Summary has a Tensor.proto containing the input Tensor.

Args
name	A name for the generated node. Will also serve as the series name in TensorBoard.
tensor	A real numeric Tensor containing a single value.
collections	Optional list of graph collections keys. The new summary op is added to these collections. Defaults to [GraphKeys.SUMMARIES].
family	Optional; if provided, used as the prefix of the summary tag name, which controls the tab name used for display on Tensorboard.

Returns
A scalar Tensor of type string. Which contains a Summary protobuf.

Raises
ValueError	If tensor has the wrong shape or type.