事实上,你几乎从来不希望你的程序从第一行代码开始,简单地执行每一行,一直到最后。流程控制语句可以决定在什么条件下执行哪些Python指令。 这些流程控制语句直接对应于流程图中的符号,所以我将提供本章中讨论的代码的流程图版本。图 2-1 显示了下雨时该做什么的流程图。沿着箭头所指的路线从头到尾走。 图2-1:告诉...
1. Python数据类型(6个) 1.1 数值型(number) 1.2 字符型(string) 字符串常用方法 转义字符 可迭代性 f-string 1.3 列表(list) 1.4 字典(dictionary) 1.5 集合(set) 1.6 元组(tuple) 1.7 内存视图Memoryview 2. 动态引用、强类型 3. 二元运算符和比较运算 4. 标量类型 5. 三元表达式 ...
print("At least one condition is True") if all(conditions): print("All conditions are True") 使用dict.get()避免KeyError 在访问字典的键时,如果该键不存在,使用dict[key]会引发KeyError。为了避免这种情况,可以使用dict.get(key, default_value),其中default_value是当键不存在时返回的默认值。 python复...
When we string operators together - Python must know which one to do first,which is called "operator precedence" Parenthesis---Power---Multiplication---Addition---Left to Right What does "Type" Mean? In Python variables,literals,and constants have a "type". Python knows the difference between...
if condition_1: statement_1 elif condition_2: statement_2 ... elif condition_i: statement_i else: statement_n 整个条件语句是顺序执行的,如果遇到一个条件满足,比如condition_i满足时,在执行完statement_i后,便会退出整个if、elif、else条件语句,而不会继续向下执行。这个语句在工作中很常用,比如下面的...
您清楚三元运算符的工作原理吗?基本上,name = something if condition else something-else。因此,如果condition评估为True,则将name分配为something,如果condition评估为False,则将something-else分配给name。 现在您已经了解了如何控制代码的路径,让我们继续下一个主题:循环。
elif another_condition: # 如果上一个条件不满足,但是这个条件满足时执行的代码块 # elif子句是可选的,可以有一个或多个 else: # 如果上面的条件都不满足时执行的代码块 # else子句也是可选的 Python使用缩进来表示代码块的层次结构,因此在if语句中,每个代码块都必须有相同的缩进级别。
Previously, it was possibly for users to create provisioning configurations for ComputeTarget's that didn't satisfy the password strength requirements for the admin_user_password field (that is, that they must contain at least 3 of the following: One lowercase letter, one uppercase lett...
state) >>> 'C' # Conditions can be passed to 'add_ordered_transitions' as well # If one condition is passed, it will be used for all transitions machine = Machine(states=states, initial='A') machine.add_ordered_transitions(conditions='check') # If a list is passed, it must contain...
Currently, this means, you need to use one of these compilers: The MinGW64 C11 compiler, on Windows, must be based on gcc 11.2 or higher. It will beautomaticallydownloaded if no usable C compiler is found, which is the recommended way of installing it, as Nuitka will also upgrade it fo...