条件语句（conditionalstatements）可以帮助检查条件并相应修改程序动作，如if语句：if之后的布尔表达式称之为条件（condition），若为true，则后面缩进的语句（如上print）会执行，否则不会有任何动作。if语句和函数定义有相同结构：header后有一个缩进的body。此类语句称之为复合语句（compoundstatements）。body中不限制语...
最简单的形式是 if 语句: if x > 0: print('x is positive') 1. 2. if 之后的布尔表达式被称作条件(condition)。 如果它为真,则缩进的语句会被执行。 如果不是,则什么也不会发生。 if 语句和函数定义有相同的结构:一个语句头跟着一个缩进的语句体。 类似的语句被称作复合语句(compound statements)。 ...
a header and an indented suite of statements is called a clause. A compound statement consists of one or more clauses: 1.5.3 Defining Functions II: Local Assignment The effect of anassignment statementis to bind a name to a value in the first frame of the current environment. As a conseq...
Python has simple and compound statements. A simple statement is a construct that occupies a single logical line, like an assignment statement. A compound statement is a construct that occupies multiple logical lines, such as a for loop or a conditional statement. An expression is a simple ...
否则: print('能被 2 整除但不能被 3 整除') 否则如果 x%3 == 0: print('能被 3 整除但不能被 2 整除')py The `elif` in the above code stands for “else if.” It is often convenient to use a **compound Boolean expression** in the test of a conditional, for example,如果 x <...
This issue becomes critical when the asserted conditions involve too much logic, such as long compound conditions, long-running predicate functions, and classes implying a costly instantiation process. Assertions can impact your code’s performance in two main ways. They will: Take time to execute ...
通常不推荐复合语句(Compound statements: 多条语句写在同一行)。 # Yesif foo == 'blah': do_blah_thing() do_one() do_two() do_three()# Noif foo == 'blah': do_blah_thing() do_one(); do_two(); do_three() 尽管有时可以在if/for/while 的同一行跟一小段代码,但绝不要跟多个子句...
Whitespace in Expressions and Statements PEP 8: Avoid extraneous whitespace in the following situations: - Immediately inside parentheses, brackets or braces. Yes: spam(ham[1], {eggs: 2}) No: spam( ham[ 1 ], { eggs: 2 } ) - Immediately before a comma,semicolon, or colon: ...
# Add some extra indentation on the conditional continuation line.if (this_is_one_thing and that_is_another_thing):do_something()右边括号也可以另起一行。有两种格式，建议第2种。# 右括号不回退，个人不推荐 my_list = [1, 2, 3,4, 5, 6,]result = some_function_that_takes_arguments('a',...
Variable names can be rebound, by invoking new assignments statements. For exampke, if we now execute:Radius=14.3 Note that this doesn't change the value associated with area.(容易错误的地方) Non-scalar objects We will see many different kinds of compound objects ...