最常用的结构是if-else,具有以下语法: if [condition]: __execution if ture__ else: __execution if false__ 例如,如果我们要打印数字N是偶数还是奇数: if N%2 == 0: 'Even' else: print 'Odd' 现在,你已经熟悉Python的基础知识了,我们进一步了解一下,如果必须执行以下任务,该怎么办? 1.两个矩阵相乘...
octave 中也有内联(inline)函数,例如将如下方程组: \[\left\{\begin{aligned} &\sin x_1 + x_2 + x_3^2e^{x_1} - 4 = 0\\ &x_1 + x_2x_3 = 0\\ &x_1x_2x_3 = -2 \end{aligned}\right. \] 转化为下面的形式函数: f = @(x) [sin(x(1)) + x(2) + x(3)^2*exp(x...
name="ali"age=22# bad practicesifname:print(name)ifname and age>18:print("user is verified") 但是更好的处理方法如下: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 # a better approachprint(nameifnameelse"")""" here you have to define the else condition too"""# good practice name...
if/elif/else while 和for 循环 基础数学运算符 选自math 和cmath 模块的函数 元组 详情请参阅 Numba 手册。 练习:使用 GPU 加速函数 我们来使用 GPU 加速“零抑制”函数。这是处理波形的一个常见运算:将所有低于某绝对量的样本值强制设为零,从而消除低振幅噪音。下面就让我们创建一些样本数据: In [ ] # Th...
strip().split(':'): if word not in d: d[word] = 1 else: d[word] += 1 如果我们使用前面介绍的defaultdict,代码能够减少3行,会被认为更加Pythonic。如下所示: d = defaultdict(int) with open('/etc/passwd') as f: for line in f: for word in line.strip().split(':'): d[word] +...
df.info() <class 'pandas.core.frame.DataFrame'> RangeIndex: 6040 entries, 0 to 6039 Data columns (total 5 columns): UserID 6040 non-null int64 Gender 6040 non-null object Age 6040 non-null int64 Occupation 6040 non-null int64 Zip-code 6040 non-null object dtypes: int64(3), object(2...
if condition1: statement1elif condition2: statement2else: statement3 for item in sequence: statement while condition: statement range(5)产生一个从0到5且间隔为1的整数列表[0,1,2,3,4] break从最内层for循环或while循环中跳出 continue继续执行下一次循环 pass占位符 enumerate()and zip() for i,item...
foo = bar if baz else 10 In JavaScript, the equivalent logic would be written as follows:var foo = baz ? bar : 10 Which one looks cleaner is subject to personal preference (I'm used to seeing condition first in most of the if statements, so the second way makes more sense to me)...
Also True if empty. Conditional Expression <obj> = <exp> if <condition> else <exp> # Only one expression is evaluated. >>> [i if i else 'zero' for i in (0, 1, 2, 3)] # `any([0, '', [], None]) == False` ['zero', 1, 2, 3] And, Or <obj> = <exp> and <...
start to use those objects by applying logic within your code, such as executing a task or creating an object when a particular condition is true (or not true!). Conditionals are a key part of applying logicwithinyour code, and understanding conditionals starts with understanding the if stateme...