ad multiclass target names encoder to ints

config_examples/config_freqai.example.json

@@ -79,7 +79,8 @@
             "test_size": 0.33,
             "random_state": 1
         },
-        "model_training_parameters": {}
+        "model_training_parameters": {},
+        "multiclass_target_names": ["down", "neither", "up"]
     },
     "bot_name": "",
     "force_entry_enable": true,

freqtrade/freqai/prediction_models/PyTorchClassifierMultiTarget.py

@@ -1,6 +1,6 @@
 import logging
 
-from typing import Any, Dict, Tuple
+from typing import Any, Dict, Tuple, List
 import numpy.typing as npt
 
 import numpy as np
@@ -9,6 +9,7 @@ import torch
 from pandas import DataFrame
 from torch.nn import functional as F
 
+from freqtrade.exceptions import OperationalException
 from freqtrade.freqai.data_kitchen import FreqaiDataKitchen
 
 from freqtrade.freqai.base_models.BasePyTorchModel import BasePyTorchModel
@@ -23,13 +24,23 @@ class PyTorchClassifierMultiTarget(BasePyTorchModel):
 
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
-        # todo move to config
-        self.labels = ['0.0', '1.0', '2.0']
-        self.n_hidden = 1024
-        self.max_iters = 100
-        self.batch_size = 64
-        self.learning_rate = 3e-4
-        self.eval_iters = 10
+        self.multiclass_names = self.freqai_info["multiclass_target_names"]
+        if not self.multiclass_names:
+            raise OperationalException(
+                "Missing 'multiclass_names' in freqai_info,"
+                " multi class pytorch model requires predefined list of"
+                " class names matching the strategy being used"
+            )
+
+        self.class_name_to_index = {s: i for i, s in enumerate(self.multiclass_names)}
+        self.index_to_class_name = {i: s for i, s in enumerate(self.multiclass_names)}
+
+        model_training_parameters = self.freqai_info["model_training_parameters"]
+        self.n_hidden = model_training_parameters.get("n_hidden", 1024)
+        self.max_iters = model_training_parameters.get("max_iters", 100)
+        self.batch_size = model_training_parameters.get("batch_size", 64)
+        self.learning_rate = model_training_parameters.get("learning_rate", 3e-4)
+        self.eval_iters = model_training_parameters.get("eval_iters", 10)
 
     def fit(self, data_dictionary: Dict, dk: FreqaiDataKitchen, **kwargs) -> Any:
         """
@@ -37,12 +48,13 @@ class PyTorchClassifierMultiTarget(BasePyTorchModel):
         :param tensor_dictionary: the dictionary constructed by DataHandler to hold
                                 all the training and test data/labels.
         """
-        n_features = data_dictionary['train_features'].shape[-1]
 
+        self.encode_classes_name(data_dictionary, dk)
+        n_features = data_dictionary['train_features'].shape[-1]
         model = PyTorchMLPModel(
             input_dim=n_features,
             hidden_dim=self.n_hidden,
-            output_dim=len(self.labels)
+            output_dim=len(self.multiclass_names)
         )
         model.to(self.device)
         optimizer = torch.optim.AdamW(model.parameters(), lr=self.learning_rate)
@@ -87,9 +99,34 @@ class PyTorchClassifierMultiTarget(BasePyTorchModel):
 
         logits = self.model.model(dk.data_dictionary["prediction_features"])
         probs = F.softmax(logits, dim=-1)
-        label_ints = torch.argmax(probs, dim=-1)
+        predicted_classes = torch.argmax(probs, dim=-1)
+        predicted_classes_str = self.decode_classes_name(predicted_classes)
 
-        pred_df_prob = DataFrame(probs.detach().numpy(), columns=self.labels)
-        pred_df = DataFrame(label_ints, columns=dk.label_list).astype(float).astype(str)
+        pred_df_prob = DataFrame(probs.detach().numpy(), columns=self.multiclass_names)
+        pred_df = DataFrame(predicted_classes_str, columns=[dk.label_list[0]])
         pred_df = pd.concat([pred_df, pred_df_prob], axis=1)
         return (pred_df, dk.do_predict)
+
+    def encode_classes_name(self, data_dictionary: Dict[str, pd.DataFrame], dk: FreqaiDataKitchen):
+        """
+        encode class name str -> int
+        assuming first column of *_labels data frame to contain class names
+        """
+        target_column_name = dk.label_list[0]
+        for split in ["train", "test"]:
+            label_df = data_dictionary[f"{split}_labels"]
+            self.assert_valid_class_names(label_df[target_column_name])
+            label_df[target_column_name] = list(
+                map(lambda x: self.class_name_to_index[x], label_df[target_column_name])
+            )
+
+    def assert_valid_class_names(self, labels: pd.Series):
+        non_defined_labels = set(labels) - set(self.multiclass_names)
+        if len(non_defined_labels) != 0:
+            raise OperationalException(
+                f"Found non defined labels {non_defined_labels} ",
+                f"expecting labels {self.multiclass_names}"
+            )
+
+    def decode_classes_name(self, classes: List[int]) -> List[str]:
+        return list(map(lambda x: self.index_to_class_name[x], classes))