Use python script for generating list.eval and list.train.

This decreases dependency on `bc` program and solves the problem with EOL on Windows.

Makefile

@@ -194,22 +194,7 @@ $(OUTPUT_DIR):
 
 $(OUTPUT_DIR)/list.eval \
 $(OUTPUT_DIR)/list.train: $(ALL_LSTMF) | $(OUTPUT_DIR)
-	@total=$$(wc -l < $(ALL_LSTMF)); \
-	  train=$$(echo "$$total * $(RATIO_TRAIN) / 1" | bc); \
-	  test "$$train" = "0" && \
-	    echo "Error: missing ground truth for training" && exit 1; \
-	  eval=$$(echo "$$total - $$train" | bc); \
-	  test "$$eval" = "0" && \
-	    echo "Error: missing ground truth for evaluation" && exit 1; \
-	  set -x; \
-	  head -n "$$train" $(ALL_LSTMF) > "$(OUTPUT_DIR)/list.train" && \
-	  tail -n "$$eval" $(ALL_LSTMF) > "$(OUTPUT_DIR)/list.eval"
-ifeq (Windows_NT, $(OS))
-	dos2unix "$(ALL_LSTMF)"
-	dos2unix "$(OUTPUT_DIR)/list.train"
-	dos2unix "$(OUTPUT_DIR)/list.eval"
-endif
-
+	$(PY_CMD) generate_eval_train.py $(ALL_LSTMF) $(RATIO_TRAIN)
 
 ifdef START_MODEL
 $(DATA_DIR)/$(START_MODEL)/$(MODEL_NAME).lstm-unicharset:

generate_eval_train.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import pathlib
+import sys
+
+
+def split_file(input_file, ratio):
+    """
+    Splits a text file into list.train and  list.eval with lines ratio.
+    """
+    if not isinstance(input_file, pathlib.Path):
+        input_file = pathlib.Path(input_file)
+    if not input_file.exists():
+        print(f"'{input_file}' not exists!")
+        return False
+    lines = input_file.read_text().splitlines()
+
+    split_point = int(ratio * len(lines))
+    output_dir = input_file.resolve().parent
+    train_list = pathlib.Path(output_dir, 'list.train')
+    eval_list = pathlib.Path(output_dir, 'list.eval')
+
+    with open(train_list, 'w', newline='\n') as f1, open(
+        eval_list, 'w', newline='\n'
+    ) as f2:
+        f1.writelines(lines[:split_point])
+        f2.writelines(lines[split_point:])
+    return True
+
+
+ratio = 0.95
+input_file = None
+if len(sys.argv) > 1:
+    input_file = sys.argv[1]
+if len(sys.argv) > 2:
+    ratio = float(sys.argv[2])
+
+split_file(input_file, ratio)