Working summary [skip ci]

lib/tensorflow/keras/layers/dense.rb

@@ -22,15 +22,17 @@ def build(input_shape)
             @bias = nil
           end
 
+          @output_shape = [last_dim, @units]
+
           @built = true
         end
 
         def output_shape
-          []
+          @output_shape
         end
 
         def count_params
-          0
+          @units + @kernel.shape.inject(&:*)
         end
 
         def call(inputs)

lib/tensorflow/keras/layers/dropout.rb

@@ -5,13 +5,17 @@ class Dropout
         def initialize(rate)
         end
 
+        def build(input_shape)
+          @output_shape = input_shape
+        end
+
         def call(inputs)
           # TODO implement
           TensorFlow.identity(inputs)
         end
 
         def output_shape
-          [] # TODO same as input shape
+          @output_shape
         end
 
         def count_params

lib/tensorflow/keras/models/sequential.rb

@@ -28,14 +28,21 @@ def evaluate(x, y)
 
         def summary
           sep = "_________________________________________________________________\n"
+
+          output_shape = nil
+          @layers.each do |layer|
+            layer.build(output_shape) if layer.respond_to?(:build)
+            output_shape = layer.output_shape
+          end
+
           total_params = @layers.map(&:count_params).sum
 
           summary = String.new("")
           summary << "Model: \"sequential\"\n"
           summary << sep
           summary << "Layer (type)                 Output Shape              Param #   \n"
           summary << "=================================================================\n"
-          summary << @layers.map { |l| "%-28s %-25s %-10s\n" % [l.class.name.split("::").last, l.output_shape.map { |v| v == -1 ? nil : v }.inspect, l.count_params] }.join(sep)
+          summary << @layers.map { |l| "%-28s %-25s %-10s\n" % [l.class.name.split("::").last, ([nil] + l.output_shape[1..-1]).inspect, l.count_params] }.join(sep)
           summary << "=================================================================\n"
           summary << "Total params: #{total_params}\n"
           summary << "Trainable params: #{total_params}\n"