argparse 参数管理

1. 分为 必写属性 可选属性
2. 可以设置默认值 范围 等等，e.g., 默认为0,范围必须在0~150

example 1

import argparse

# https://zhuanlan.zhihu.com/p/34395749

def cmd():
    args = argparse.ArgumentParser(description = 'Personal Information ',epilog = 'Information end ')
    #必写属性,第一位
    args.add_argument("name",         type = str,                  help = "Your name")
    #必写属性,第二位
    args.add_argument("birth",        type = str,                  help = "birthday")
    #可选属性,默认为None
    args.add_argument("-r",'--race',  type = str, dest = "race",   help = u"民族")
    #可选属性,默认为0,范围必须在0~150
    args.add_argument("-a", "--age",  type = int, dest = "age",    help = "Your age",         default = 0,      choices=range(150))
    #可选属性,默认为male
    args.add_argument('-s',"--sex",   type = str, dest = "sex",    help = 'Your sex',         default = 'male', choices=['male', 'female'])
    #可选属性,默认为None,-p后可接多个参数
    args.add_argument("-p","--parent",type = str, dest = 'parent', help = "Your parent",      default = "None", nargs = '*')
    #可选属性,默认为None,-o后可接多个参数
    args.add_argument("-o","--other", type = str, dest = 'other',  help = "other Information",required = False,nargs = '*')

    args = args.parse_args() #返回一个命名空间,如果想要使用变量,可用args.attr
    print("argparse.args=",args,type(args))
    print('name = %s'%args.name)
    d = args.__dict__
    for key,value in d.items():
        print('%s = %s'%(key,value))

if __name__=="__main__":
    cmd()

python args1.py ltt 1996

argparse.args= Namespace(age=0, birth='1996', name='ltt', other=None, parent='None', race=None, sex='male') <class 'argparse.Namespace'>

name = ltt

name = ltt
birth = 1996
race = None
age = 0
sex = male
parent = None
other = None

example 2 

import argparse

# https://www.jianshu.com/p/b8b09084bd1a

parser = argparse.ArgumentParser()

parser.add_argument("--echo", type=str, help="echo the string you use here")
parser.add_argument("--square", type=int, help="display a square of a given number")
args = parser.parse_args()

print(args.echo)
print(args.square**2)

python args2.py --echo ok --square 6

ok
36