Numpy pandas 数据读取写入

import pandas as pd
import os
import numpy as np

def read_folder(file_dir):
    L=[]
    for root,dirs,files in os.walk(file_dir):
        for file in files:
            L.append(file)
            L.sort()
    return L

if __name__=='__main__':
    L=read_folder('/home/data/df_pcl/data/submit_example')
    total_point=[]
    print('the number of test:'+str(len(L)))
    count=1
    for j in range(len(L)):
        csv_data=pd.read_csv('/home/data/df_pcl/data/submit_example/'+str(L[j]))
        csv_data=np.array(csv_data)
        print('file order'+str(count)+', process '+str(L[j])+', total point '+str(csv_data.shape[0]))
        csv_data[:]=3
        csv_data=csv_data.flatten()
        csv_data=csv_data.tolist()
        pd_data=pd.DataFrame(csv_data,columns=['0'])
        pd_data.to_csv('/home/data/df_pcl/data/submit_example_our/'+str(L[j]),encoding='utf-8',index=False)
        total_point.append(len(csv_data))
        count=count+1
    average_point=float(np.sum(total_point))/(len(L))
    print('average_point: '+str(average_point))