print(emptyDict) # 查看字典的数量 print("Length:", len(emptyDict)) # 查看类型 print(type(emptyDict)) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 输出结果: {} Length: 0 <class 'dict'> 1. 2. 3. 访问字典里的值 tinydict = {'Name': '?abc!', 'Age': 7, 'Class': '...
type()返回对象类型a = list() print(type(a)) # <class 'list'>回到顶部 dir()dir()是自省的一个重要函数,返回列表,列出对象所拥有的属性和方法a = list() print(dir(a)) # ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__dir__', # '__doc_...
成功解决Python中出现的TypeError: object of type 'zip' has no len() 不罗嗦,直接解决问题! 问题:TypeError: object of type 'zip' has no len() 参考国外网友回答: 解决方案:将 print(len(training_data)) 改为 print(list(training_data)) 大功告成!不用谢,我叫leifeng!... ...
#定义一个变量名为name 变量值为scottname ="scott"print(name,type(name))#定义一个变量名为age 变量值为20age ="20"print(age,type(age))#定义一个变量名为height 变量值为180cmheight ="180cm"print(height,type(height))#定义一个变量名为weight 变量值为70kgweight ="70kg"print(weight,type(weight)...
) S.split([sep [,maxsplit]]) -> list of strings #sep为分隔符,默认为空格 最大分隔次数 Return a list of the words in the string S, using sep as the delimiter string. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace ...
Hello, codedamn learners! Today, we are going to delve deep into a ubiquitous yet crucial aspect of Python programming: checking if a list is empty. This task may seem trivial, but understanding it thoroughly can make a significant difference in your
shape和dtype属性 ndarray是numpy的多维数组对象,是numpy类库中主要的数据结构,它有两个重要的属性,shape和dtype,shape是描述数组维度的元组,dtype用于说明数组数据类型。 data = [1,2,3,4,5] arr1 = np.array(data) arr1 Out[6]: array([1, 2, 3, 4, 5]) ...
Astringis a Python data type that’s used to represent a piece of text. It’s written between quotes, either double quotes or single quotes and can be as short as zero characters, or empty string, or as long as you wish. Strings can beconcatenatedto build longer strings using the plus...
In[1]:b=[1,2,3]In[2]:b?Type:list String form:[1,2,3]Length:3Docstring:Built-inmutable sequence.If no argument is given,the constructor creates anewemptylist.The argument must be an iterableifspecified.In[3]:print?Docstring:print(value,...,sep=' ',end='\n',file=sys.stdout,flush...
The emptiness of a list is associated to the boolean False, so you don’t have to check len(lst) == 0, but just lstor not lst 列表的空值可以利用布尔值False处理,所以不必检查len(lst) == 0,只需检查是或否就可以: lst = [] if not lst: print("list is empty") #输出: list is emp...