[python] 文件复制/路径检测

曾经终败给现在 2022-05-13 05:18 201阅读 0赞

### import shutil ###

`shutil.copytree(sourceResDir, dstResDir)`  
复制目录，olddir和newdir都只能是目录，且newdir必须不存在

文件的拷贝用`shutil.copyfile(srcFilePath,dstFilePath)`  
oldfile和newfile都只能是文件

`shutil.copy( src, dst)` 复制一个文件，到一个文件或一个目录

### import os ###

`if not os.path.exist(path)` 检测文件夹是否存在  
`os.mkdir()` 如果不存在，创建文件夹 ,mkdir只能创建最后一层的文件夹  
`os.path.exists(no_exist_file.txt)`判断文件，文件夹是否存在

import os 
    #os.walk(path)遍历文件夹，没有返回值，直接循环调用
    for root, dirs, files in os.walk(".", topdown=False):
        for name in files:
            print(os.path.join(root, name)) #文件名
        for name in dirs: # 子文件夹名
            print(os.path.join(root, name))

### csv ###

读取

with open(os.path.join('/hdd/NTU_RGBD', 'split_ntu_cs_frames.csv'), 'r') as fin:
            reader = csv.reader(fin)
            data = list(reader)
            root_path = '/hdd/NTU_RGBD/cs_frames'
            count = 0
            for item in data:
                print item
                origin_path = os.path.join(root_path,item[0],item[1],item[3]+'_rgb-'+item[4].zfill(4)+'.jpg')
                new_path = os.path.join('/hdd/NTU_RGBD/cs_one_frames',item[0],item[2],item[3]+'__rgb--00'+item[4]+'.jpg')
                shutil.copy(origin_path,new_path)
                count += 1
            print count

写入

with open('split_ntu_cs_frames.csv', 'w') as fout:
            writer = csv.writer(fout)
            writer.writerows(frames)

`write_row write_rows` dict

for train_sample in train:
    				splits[i]['train'].extend(train_sample)
    			for test_sample in test:
    				splits[i]['test'].extend(test_sample)
    
    	with open('setting_2.csv','w') as csvfile:
    		header = ['test','train']
    		writer = csv.DictWriter(csvfile,fieldnames =header)
    		writer.writeheader()
    		# for cross_val in splits:
    		writer.writerows(splits) ，list中的每个元素都是字典
    
    import csv
    
    with open('names.csv', 'w') as csvfile:
        fieldnames = ['first_name', 'last_name']
        writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
    
        writer.writeheader()
        writer.writerow({'first_name': 'Baked', 'last_name': 'Beans'})
        writer.writerow({'first_name': 'Lovely', 'last_name': 'Spam'})
        writer.writerow({'first_name': 'Wonderful', 'last_name': 'Spam'})
    ...
    first_name,last_name
    Baked,Beans
    Lovely,Spam
    Wonderful,Spam
    
    >>> import csv
    >>> with open('names.csv') as csvfile:
    ...     reader = csv.DictReader(csvfile)
    ...     for row in reader:
    ...         print(row['first_name'], row['last_name'])
    ...
    
    
    Baked Beans
    Lovely Spam
    Wonderful Spam

读取的时候 ， reader是一个对象，不是一个列表，该怎么办？  
如果用for循环取出的话，每一个row是一个字典。  
字典中原来存储的array 变成了字符串，2-d array 变成了换行符+list+字符串

with open(csv_name,'r') as csv_file:
                pred_true= csv.DictReader(csv_file)
    
                for row in pred_true:                
                    y_pred_str = row['y_pred']
                    y_pred_str = y_pred_str.strip('[]').split(' ') 
                    for i in y_pred_str:  # 有些是空字符，有些还有换行符
                        if i != '':  
                            y_pred_list.append(eval(i))

### glob ###

import glob
    glob.glob()
    glob给出的不是本机的绝对录路径，而是所给path的最深路径