list_example = [1, 2, 2, 3, 3, 3] print(set(list_example)) # {1, 2, 3} str_example = "banana" print(set(str_example)) # {'a', 'b', 'n'} dict() - 创建字典 dict() 函数可以从键值对序列创建字典。 list_of_tuples = [("name", "Alice"), ("age", 25)] print(dict...
nums=[1,2,3,4]print(*nums)# 输出：1 2 3 4# 用解包合并列表list1=[1,2]list2=[3,4]me...
reversed(iterable) - 创建一个迭代器可以反向遍历iterable list(iterable) - 创建一个list,得到iterable中的所有元素 tuple(iterable) - 创建一个tuple,包含iterable中的所有元素 sorted(iterable) - 创建一个排好序的list,包含iterable中的所有元素 Generators 生成器 一个生成器函数返回一个特殊的迭代器类型,叫做生...
Aloopis a sequence of instructions that is continually repeated until a certain condition is reached. For instance, we have a collection of items and we create a loop to go through all elements of the collection. In Python, we can loop over list elements with for and while statements, and...
# Detect repeated values due to over polling if data[i] == data[i - 1]: repeats += 1 end = time.monotonic() total_time = end - start # Make into numpy array and reshape to (128,128) a = np.array(data).reshape((128,128)) ...
for target in object:# Assign object items to targetstatements# Repeated loop body: use targetelse:# Optional else partstatements# If we didn't hit a 'break' lambda 迭代遍历 map() 会根据提供的函数对"指定序列"做映射。 <返回list类型> = map(function, iterable, ...) ...
values. The most versatile is the *list*, which can be written as a list of comma-separated values (items) between square brackets. List items need not all have the same type. :: Python 有几个 *复合* 数据类型,用于分线其它的值。最通用的是 *list* (列 ...
{} movie_ids = list(df[0].values) movie_name = list(df[1].values) for k,v in zip(movie_ids,movie_name): movie_dict[k] = v return movie_dict # Function to create training validation and test data def train_val(df,val_frac=None): X,y = df[['userID','movieID']].values,...
In the rest of the examples, you create other variables that point to other types of objects, such as a string, tuple, and list, respectively. You’ll use the assignment operator in many of the examples that you’ll write throughout this tutorial. More importantly, you’ll use this opera...
list的reverse函数:反转一个list, 他的返回值为none 比如上面的列表a b = a. reverse() print b 输出的内容是None 直接看a列表变量能看到翻转的效果。 1.内置list方法 a=”asd” list(a) 返回一个列表,参数是可迭代对象,里面输出的内容还是保持了传入的可迭代对象的元素顺序。