diff --git a/README.md b/README.md
index 0f2697a..f3d5d25 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ $ python evaluate_xaj.py --exp expcamels001
 Run the following code to see the results of the evaluation:
 
 ```Shell
-$ python post_process.py --exp expcamels001
+$ python visualize.py --exp expcamels001
 ```
 
 You will see the results in the `example` directory.
diff --git a/hydromodel/datasets/data_preprocess.py b/hydromodel/datasets/data_preprocess.py
index 14ff720..210164b 100644
--- a/hydromodel/datasets/data_preprocess.py
+++ b/hydromodel/datasets/data_preprocess.py
@@ -1,7 +1,7 @@
 """
 Author: Wenyu Ouyang
 Date: 2022-10-25 21:16:22
-LastEditTime: 2024-03-27 16:31:55
+LastEditTime: 2024-03-27 18:17:14
 LastEditors: Wenyu Ouyang
 Description: preprocess data for models in hydro-model-xaj
 FilePath: \hydro-model-xaj\hydromodel\datasets\data_preprocess.py
@@ -13,10 +13,12 @@
 from hydrodataset import Camels
 import numpy as np
 import pandas as pd
+from pint import UnitRegistry
 from sklearn.model_selection import KFold
 import xarray as xr
 
 from hydrodata.utils.utils import streamflow_unit_conv
+from hydrodata.cleaner.dmca_esr import rainfall_runoff_event_identify
 
 from hydromodel import CACHE_DIR, SETTING
 from hydromodel.datasets import *
@@ -432,7 +434,7 @@ def get_ts_from_diffsource(data_type, data_dir, periods, basin_ids):
     data_dir
         The directory of the data source
     periods
-        The periods of the time series data
+        The periods of the time series data, [start_date, end_date]
     basin_ids
         The ids of the basins
 
@@ -473,6 +475,7 @@ def get_ts_from_diffsource(data_type, data_dir, periods, basin_ids):
         r_mmd = streamflow_unit_conv(qobs_, basin_area, target_unit=target_unit)
         ts_data[flow_name] = r_mmd[flow_name]
         ts_data[flow_name].attrs["units"] = target_unit
+        ts_data = ts_data.sel(time=slice(periods[0], periods[1]))
     else:
         raise NotImplementedError(
             "You should set the data type as 'camels' or 'owndata'"
@@ -519,3 +522,23 @@ def cross_val_split_tsdata(
         # cross validation
         train_and_test_data = cross_valid_data(ts_data, periods, warmup, cv_fold)
     return train_and_test_data
+
+
+def get_rr_events(rain, flow, basin_area):
+    ureg = UnitRegistry()
+    # trans unit to mm/day
+    flow_threshold = streamflow_unit_conv(
+        np.array([100]) * ureg.m**3 / ureg.s,
+        basin_area.isel(basin=0).to_array().to_numpy() * ureg.km**2,
+        target_unit="mm/h",
+    )
+    rr_events = {}
+    for basin in basin_area.basin.values:
+        rr_event = rainfall_runoff_event_identify(
+            rain.sel(basin=basin).to_series(),
+            flow.sel(basin=basin).to_series(),
+            multiple=1,
+            flow_threshold=flow_threshold[0],
+        )
+        rr_events[basin] = rr_event
+    return rr_events
diff --git a/hydromodel/datasets/data_postprocess.py b/hydromodel/datasets/data_visualize.py
similarity index 91%
rename from hydromodel/datasets/data_postprocess.py
rename to hydromodel/datasets/data_visualize.py
index 1871fc0..8232f0b 100644
--- a/hydromodel/datasets/data_postprocess.py
+++ b/hydromodel/datasets/data_visualize.py
@@ -1,11 +1,11 @@
 """Show results of calibration and validation."""
 
 import os
-from matplotlib import pyplot as plt
+from matplotlib import dates, pyplot as plt
 import numpy as np
 import pandas as pd
 
-from hydroutils import hydro_file, hydro_stat
+from hydroutils import hydro_file, hydro_stat, hydro_plot
 
 
 def plot_sim_and_obs(
@@ -54,6 +54,32 @@ def plot_train_iteration(likelihood, save_fig):
     plt.close()
 
 
+def plot_rr_events(rr_events, rain, flow, save_dir=None):
+    for i in range(len(rr_events)):
+        beginning_time = rr_events["BEGINNING_RAIN"].iloc[i]
+        end_time = rr_events["END_FLOW"].iloc[i]  # Ensure this column exists
+
+        # Filter data for the specific time period
+        filtered_rain_data = rain.sel(time=slice(beginning_time, end_time))
+        filter_flow_data = flow.sel(time=slice(beginning_time, end_time))
+
+        # Plotting
+        hydro_plot.plot_rainfall_runoff(
+            filtered_rain_data.time.values,
+            filtered_rain_data.values,
+            [filter_flow_data.values],
+            title=f"Rainfall-Runoff Event {i}",
+            leg_lst=["Flow"],
+            xlabel="Time",
+            ylabel="Flow (mm/h)",
+        )
+        if save_dir:
+            if not os.path.exists(save_dir):
+                os.makedirs(save_dir)
+            save_fig = os.path.join(save_dir, f"rr_event_{i}.png")
+            plt.savefig(save_fig, bbox_inches="tight")
+
+
 def show_events_result(
     warmup_length,
     save_dir,
diff --git a/hydromodel/trainers/calibrate_ga.py b/hydromodel/trainers/calibrate_ga.py
index 800c18f..0c55e38 100644
--- a/hydromodel/trainers/calibrate_ga.py
+++ b/hydromodel/trainers/calibrate_ga.py
@@ -20,7 +20,7 @@
 from hydroutils import hydro_file, hydro_stat
 
 
-from hydromodel.datasets.data_postprocess import plot_sim_and_obs, plot_train_iteration
+from datasets.data_visualize import plot_sim_and_obs, plot_train_iteration
 from hydromodel.models.model_config import read_model_param_dict
 from hydromodel.models.model_dict import MODEL_DICT, rmse43darr
 
diff --git a/hydromodel/trainers/train.py b/hydromodel/trainers/train.py
deleted file mode 100644
index 66bf12f..0000000
--- a/hydromodel/trainers/train.py
+++ /dev/null
@@ -1,53 +0,0 @@
-"""
-Author: Wenyu Ouyang
-Date: 2022-08-06 18:39:15
-LastEditTime: 2024-03-27 09:41:06
-LastEditors: Wenyu Ouyang
-Description: We want to build a trainer class for calibration but not done yet.
-FilePath: \hydro-model-xaj\hydromodel\trainers\train.py
-Copyright (c) 2021-2022 Wenyu Ouyang. All rights reserved.
-"""
-
-import matplotlib
-import os
-import sys
-from pathlib import Path
-
-sys.path.append(os.path.dirname(Path(os.path.abspath(__file__)).parent))
-
-matplotlib.use("Agg")
-exp = "exp61561"
-reps = [5000, 10000]
-ngs = [1000, 2000]
-book = "HF"
-source = "sources"
-
-
-class Trainer:
-    # TODO: build a trainer class for calibration
-    def __init__(self, exp, book, source, rep, ngs):
-        self.exp = exp
-        self.warmup_length = 365
-        self.model = {
-            "name": "xaj_mz",
-            "source_type": source,
-            "source_book": book,
-        }
-        self.algorithm = {
-            "name": "SCE_UA",
-            "random_seed": 1234,
-            "rep": rep,
-            "ngs": ngs,
-            "kstop": int(rep / 5),
-            "peps": 0.001,
-            "pcento": 0.001,
-        }
-        self.comment = "{}{}rep{}ngs{}".format(book, source, rep, ngs)
-
-
-for i in range(len(reps)):
-    for j in range(len(ngs)):
-        rep = reps[i]
-        ng = ngs[j]
-        xaj_calibrate = Trainer(exp, book, source, rep, ng)
-        # evaluate(xaj_calibrate)
diff --git a/scripts/preprocess.py b/scripts/preprocess.py
new file mode 100644
index 0000000..02c5eb6
--- /dev/null
+++ b/scripts/preprocess.py
@@ -0,0 +1,94 @@
+"""
+Author: Wenyu Ouyang
+Date: 2024-03-25 09:21:56
+LastEditTime: 2024-03-27 18:20:38
+LastEditors: Wenyu Ouyang
+Description: preprocess data in an exp before training
+FilePath: \hydro-model-xaj\scripts\preprocess.py
+Copyright (c) 2023-2024 Wenyu Ouyang. All rights reserved.
+"""
+
+from pathlib import Path
+import sys
+import os
+import argparse
+
+current_script_path = Path(os.path.realpath(__file__))
+repo_path = current_script_path.parent.parent
+sys.path.append(str(repo_path))
+from hydromodel.datasets.data_visualize import plot_rr_events
+from hydromodel.datasets.data_preprocess import (
+    get_basin_area,
+    get_ts_from_diffsource,
+    get_rr_events,
+)
+
+
+def main(args):
+    data_path = args.data_dir
+    data_type = args.data_type
+    basin_ids = args.basin_id
+    periods = args.period
+    exp = args.exp
+    where_save = Path(os.path.join(repo_path, "result", exp))
+    if os.path.exists(where_save) is False:
+        os.makedirs(where_save)
+    ts_data = get_ts_from_diffsource(data_type, data_path, periods, basin_ids)
+    basin_area = get_basin_area(data_type, data_path, basin_ids)
+    rr_events = get_rr_events(ts_data["prcp"], ts_data["flow"], basin_area)
+    for basin, event in rr_events.items():
+        basin_rr_dir = os.path.join(where_save, f"{basin}_rr_events")
+        plot_rr_events(
+            event,
+            ts_data["prcp"].sel(basin=basin),
+            ts_data["flow"].sel(basin=basin),
+            basin_rr_dir,
+        )
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Prepare data.")
+    parser.add_argument(
+        "--data_type",
+        dest="data_type",
+        help="CAMELS dataset or your own data, such as 'camels' or 'owndata'",
+        # default="camels",
+        default="owndata",
+        type=str,
+    )
+    parser.add_argument(
+        "--data_dir",
+        dest="data_dir",
+        help="The directory of the CAMELS dataset or your own data, for CAMELS,"
+        + " as we use SETTING to set the data path, you can directly choose camels_us;"
+        + " for your own data, you should set the absolute path of your data directory",
+        # default="camels_us",
+        default="C:\\Users\\wenyu\\OneDrive\\data\\biliuhe",
+        type=str,
+    )
+    parser.add_argument(
+        "--exp",
+        dest="exp",
+        help="An exp is corresponding to one data setting",
+        # default="expcamels001",
+        default="expbiliuhe001",
+        type=str,
+    )
+    parser.add_argument(
+        "--basin_id",
+        dest="basin_id",
+        help="The basins' ids",
+        # default=["01439500", "06885500", "08104900", "09510200"],
+        default=["21401550"],
+        nargs="+",
+    )
+    parser.add_argument(
+        "--period",
+        dest="period",
+        help="The whole period",
+        # default=["2007-01-01", "2014-01-01"],
+        default=["2012-06-10 00:00", "2022-08-31 23:00"],
+        nargs="+",
+    )
+    args = parser.parse_args()
+    main(args)
diff --git a/scripts/post_process.py b/scripts/visualize.py
similarity index 95%
rename from scripts/post_process.py
rename to scripts/visualize.py
index c748cdd..f781e19 100644
--- a/scripts/post_process.py
+++ b/scripts/visualize.py
@@ -1,10 +1,10 @@
 """
 Author: Wenyu Ouyang
 Date: 2022-11-19 17:27:05
-LastEditTime: 2024-03-27 16:27:03
+LastEditTime: 2024-03-27 17:54:11
 LastEditors: Wenyu Ouyang
 Description: the script to postprocess results
-FilePath: \hydro-model-xaj\scripts\post_process.py
+FilePath: \hydro-model-xaj\scripts\visualize.py
 Copyright (c) 2021-2022 Wenyu Ouyang. All rights reserved.
 """
 
@@ -15,7 +15,7 @@
 
 repo_dir = os.path.dirname(Path(os.path.abspath(__file__)).parent)
 sys.path.append(repo_dir)
-from hydromodel.datasets.data_postprocess import plot_sim_and_obs
+from hydromodel.datasets.data_visualize import plot_sim_and_obs
 from hydromodel.trainers.evaluate import Evaluator, read_yaml_config
 
 
diff --git a/test/test_data_postprocess.py b/test/test_data_postprocess.py
index 7c82f27..a3b7afd 100644
--- a/test/test_data_postprocess.py
+++ b/test/test_data_postprocess.py
@@ -14,7 +14,7 @@
 
 from hydroutils import hydro_time
 
-from hydromodel.datasets.data_postprocess import show_events_result, show_ts_result
+from hydromodel.datasets.data_visualize import show_events_result, show_ts_result
 from hydromodel.models.xaj import xaj
 from hydromodel.trainers.calibrate_sceua import calibrate_by_sceua
 from hydromodel.trainers.evaluate import _read_save_sceua_calibrated_params