// isNaN() //如果是数字,就返回false,不是就返回true var flag = isNaN(score); // if(flag){ alert("不是正确的成绩") }else{ // console.log("是数字") if(score >= 90 && score <= 100){ alert("优秀") }else if(score >= 80 && score < 90){ alert("良好") }else if(score ...
每条if语句的核心都是一个值为True或False的表达式,这种表达式被称为条件测试。Python根据条件测试的值为True还是False来决定是否执行if语句中的代码。如果条件测试的值为True,Python就执行紧跟在if语句后面的代码;如果为False,Python就忽略这些代码。 2.1 检查是否相等 大多数条件测试都将一个变量的当前值同特定值进行...
print('a'in'hello world aaa')# 结果为True print('hello'in'hello world aaa')# 结果为True print('jason'in ['jason','egon','kevin'])# 结果为True print('jason'in {'name':'jason','pwd':123})# 结果为False print('name'in {'name':'jason','pwd':123})# 结果为True # 字典参与成...
当我们需要在NaN中使用if语句时,可以使用math.isnan()函数来检查Python值是否为NaN。 具体的代码示例如下: 代码语言:txt 复制 import math value = float('nan') # 创建一个NaN值 if math.isnan(value): print("Value is NaN") else: print("Value is not NaN") 上述代码中,我们首先使用float('nan'...
在数据科学和数据分析领域,NaN(Not a Number)是一个常见的概念,它表示一个缺失或未定义的数值。在 Python 中,尤其是在使用pandas库处理数据时,NaN 值的处理尤为重要。...NaN 值的来源和影响 NaN 值可能来源于多种情况,比如数据收集过程中的遗漏、数据转换错误或者计
01 for循环 for循环是Python的一种最基本的控制结构。使用for循环的一种常见模式是使用range函数生成数值范围,然后对其进行迭代。 res = range(3) print(list(res)) #输出:[0, 1, 2] for i in range(3): print(i) '''输出: 0 1 2 ''' ...
In computer programming, the if statement allows us to create a decision making program. A decision making program runs one block of code under a condition and another block of code under different conditions. For example, If age is greater than 18, allow the person to vote. If age is ...
Python NumPy Programs » How to select elements of an array given condition? NumPy selecting specific column index per row by using a list of indexes Related Tutorials NumPy: Divide each row by a vector element Find the most frequent value in a NumPy array ...
Python program to drop row if two columns are NaN# Importing pandas package import pandas as pd # Importing numpy package import numpy as np # Creating two dictionary d = { 'a':[0.9,0.8,np.nan,1.1,0], 'b':[0.3,0.5,np.nan,1,1.2], 'c':[0,0,1.1,1.9,0.1], 'd':[9,8,0,...
Description Python version: 3.11.5 SciPy version: 1.11.3 When there are NaNs in the input, the test silently produces NaN as an output (i.e., resulting statistics and p-value). It should at least give a warning suggesting that the NaNs i...