python常用用法

获取目录下的所有文件

os.listdir()

 

>>> my_list = ['a', 'b', 'c']

>>> for idx, val in enumerate(my_list):

... print(idx, val)

 

创建文件夹

porject_path = os.getcwd()
print(porject_path)
chip_path2 = "./design_my/img_output/mask_chips/"+img_name+'/'
chip_path= os.path.join(porject_path,chip_path2)
print(chip_path)
if os.path.exists(chip_path):
   print(chip_path," had exist!")
else:
    os.makedirs(chip_path)
    print("create: ", chip_path)
mask_output = "./design_my/img_output/mask_output/"
if os.path.exists(mask_output):
    print(mask_output," had exist!")
else:
    os.makedirs(mask_output)
    print("create: ", mask_output)

create: /home/lhw/Gradute/collage/fbrs_interactive_segmentation-master/./design_my/img_output/mask_chips/000000000625/
create: ./design_my/img_output/mask_output/

 

 获取dict的第一个元素的value

d = {'a': 1, 'b': 2}
print(list(d.values())[0])
print(next(iter(d.values())))  #适用于数据量多的时候会更快

 

 

 

import os 
file_name = os.path.basename(__file__)
print(file_name)
# 输出为 test.py
file_name = file_name.split('.')[0]
print(file_name)
# 输出为 test
stem, suffix = os.path.splitext(filename) print(stem, suffix) # test .py

文件名排序

# img_path = "./openpose_data/img/COCO_train2014_000000000625.jpg"

img_paths = "./openpose_data/img/"
img_list = os.listdir(img_paths)
img_list.sort(key=lambda x: int(x[:-4]))  # 倒着数第四位'.'为分界线，按照‘.'左边的数字从小到大排序
print(img_list)

 

 

计算两个mask图像的IOU

def mask_iou(det_mask, pred_mask):
    '''
    Computes IoU between two masks
    Input: two 2D array mask
    '''
    Union = (pred_mask + det_mask) != 0
    Intersection = (pred_mask * det_mask) != 0
    return np.sum(Intersection) / np.sum(Union)