1 files changed, 127 insertions, 0 deletions
diff --git a/code/sunlab/sunflow/models/decoder.py b/code/sunlab/sunflow/models/decoder.py
new file mode 100644
index 0000000..40ea190
--- /dev/null
+++ b/code/sunlab/sunflow/models/decoder.py
@@ -0,0 +1,127 @@
+class Decoder:
+    """# Decoder Model
+
+    Constructs a decoder model with a certain depth of intermediate layers of
+    fixed size"""
+
+    def __init__(self, model_base_directory):
+        """# Decoder Model Initialization
+
+        - model_base_directory: The base folder directory where the model will
+        be saved/ loaded"""
+        self.model_base_directory = model_base_directory
+
+    def init(self):
+        """# Initialize a new Decoder
+
+        Expects a model parameters file to already exist in the initialization
+        base directory when initializing the model"""
+        from tensorflow import keras
+        from tensorflow.keras import layers
+
+        self.load_parameters()
+        assert self.depth >= 0, "Depth must be non-negative"
+        self.model = keras.models.Sequential()
+        if self.depth == 0:
+            self.model.add(
+                layers.Dense(
+                    self.data_size,
+                    input_shape=(self.latent_size,),
+                    activation=None,
+                    name="decoder_latent_vector",
+                )
+            )
+        else:
+            self.model.add(
+                layers.Dense(
+                    self.layer_size,
+                    input_shape=(self.latent_size,),
+                    activation=None,
+                    name="decoder_dense_1",
+                )
+            )
+            if self.use_leaky_relu:
+                self.model.add(layers.LeakyReLU())
+            else:
+                self.model.add(layers.ReLU())
+            if self.dropout > 0.0:
+                self.model.add(layers.Dropout(self.dropout))
+            for _d in range(1, self.depth):
+                self.model.add(
+                    layers.Dense(
+                        self.layer_size, activation=None, name=f"decoder_dense_{_d+1}"
+                    )
+                )
+                if self.use_leaky_relu:
+                    self.model.add(layers.LeakyReLU())
+                else:
+                    self.model.add(layers.ReLU())
+                if self.dropout > 0.0:
+                    self.model.add(layers.Dropout(self.dropout))
+            self.model.add(
+                layers.Dense(
+                    self.data_size, activation=None, name="decoder_output_vector"
+                )
+            )
+        self.model._name = "Decoder"
+        return self
+
+    def load(self):
+        """# Load an existing Decoder"""
+        from os import listdir
+
+        if "decoder.keras" not in listdir(f"{self.model_base_directory}/portable/"):
+            return None
+        import tensorflow as tf
+
+        self.model = tf.keras.models.load_model(
+            f"{self.model_base_directory}/portable/decoder.keras", compile=False
+        )
+        self.model._name = "Decoder"
+        return self
+
+    def save(self, overwrite=False):
+        """# Save the current Decoder
+
+        - Overwrite: overwrite any existing decoder that has been saved"""
+        from os import listdir
+
+        if overwrite:
+            self.model.save(f"{self.model_base_directory}/portable/decoder.keras")
+            return True
+        if "decoder.keras" in listdir(f"{self.model_base_directory}/portable/"):
+            return False
+        self.model.save(f"{self.model_base_directory}/portable/decoder.keras")
+        return True
+
+    def load_parameters(self):
+        """# Load Decoder Model Parameters from File
+        The file needs to have the following parameters defined:
+         - data_size: int
+         - autoencoder_layer_size: int
+         - latent_size: int
+         - autoencoder_depth: int
+         - dropout: float (set to 0. if you don't want a dropout layer)
+         - use_leaky_relu: boolean"""
+        from pickle import load
+
+        with open(
+            f"{self.model_base_directory}/portable/model_parameters.pkl", "rb"
+        ) as phandle:
+            parameters = load(phandle)
+        self.data_size = parameters["data_size"]
+        self.layer_size = parameters["autoencoder_layer_size"]
+        self.latent_size = parameters["latent_size"]
+        self.depth = parameters["autoencoder_depth"]
+        self.dropout = parameters["dropout"]
+        self.use_leaky_relu = parameters["use_leaky_relu"]
+
+    def summary(self):
+        """# Returns the summary of the Decoder model"""
+        return self.model.summary()
+
+    def __call__(self, *args, **kwargs):
+        """# Callable
+
+        When calling the decoder class, return the model's output"""
+        return self.model(*args, **kwargs)