tf.contrib.layers.joint_weighted_sum_from_feature_columns( columns_to_tensors, feature_columns, num_outputs, weight_collections=None, trainable=True, scope=None )
A restricted linear prediction builder based on FeatureColumns.
As long as all feature columns are unweighted sparse columns this computes the prediction of a linear model which stores all weights in a single variable.
columns_to_tensors: A mapping from feature column to tensors. 'string' key means a base feature (not-transformed). It can have FeatureColumn as a key too. That means that FeatureColumn is already transformed by input pipeline. For example,
inflowmay have handled transformations.
feature_columns: A set containing all the feature columns. All items in the set should be instances of classes derived from FeatureColumn.
num_outputs: An integer specifying number of outputs. Default value is 1.
weight_collections: List of graph collections to which weights are added.
Truealso add variables to the graph collection
scope: Optional scope for variable_scope.
A tuple containing:
- A Tensor which represents predictions of a linear model.
- A list of Variables storing the weights.
- A Variable which is used for bias.
ValueError: if FeatureColumn cannot be used for linear predictions.