8149fd12d6f0

1. 可调用对象 可调用对象有一下几种定义： 是一个函数指针，参考 C++ 函数指针和函数类型； 是一个具有operator()成员函数的类的对象； 可被转换成函数指针的类对...

8149fd12d6f0

你好 运行以下代码，
1）
def normal_func(arg1, arg2, arg3):
print("arg1: " + arg1)
print("arg2: " + arg2)
print("arg3: " + arg3)

normal_func("python", 1, 3)
---------------------------------------------------------------
报错：
/home/lzw/anaconda3/envs/3.8.1/bin/python /home/lzw/PycharmProjects/untitled2/test.py
arg1: python
Traceback (most recent call last):
File "/home/lzw/PycharmProjects/untitled2/test.py", line 7, in <module>
normal_func("python", 1, 3)
File "/home/lzw/PycharmProjects/untitled2/test.py", line 4, in normal_func
print("arg2: " + arg2)
TypeError: can only concatenate str (not "int") to str

Process finished with exit code 1

2）def test_kwargs(**kwargs):
if kwargs is not None:
for key, value in kwargs.iteritems():
print("{} = {}".format(key,value))
# Or you can visit kwargs like a dict() object
# for key in kwargs:
# print("{} = {}".format(key, kwargs[key]))
test_kwargs(name="python", value="5")
------------------------------------------------------------------------------------------------
报错：/home/lzw/anaconda3/envs/3.8.1/bin/python /home/lzw/PycharmProjects/untitled2/test.py
Traceback (most recent call last):
File "/home/lzw/PycharmProjects/untitled2/test.py", line 8, in <module>
test_kwargs(name="python", value="5")
File "/home/lzw/PycharmProjects/untitled2/test.py", line 3, in test_kwargs
for key, value in kwargs.iteritems():
AttributeError: 'dict' object has no attribute 'iteritems'

Process finished with exit code 1

python参数传递的*args和**kwargs

*和** 实际上真正的Python参数传递语法是*和**。*args和**kwargs只是一种约定俗成的编程实践。我们也可以写成*vars和**kvars。 *args和**...

耀凯考前突击大师

33222 5 16

8149fd12d6f0

安装包下载网址：http://eigen.tuxfamily.org/index.php?title=Main_Page在该网站中，可以下载任意版本对应的文件，本例下载了Ei...