身体质量指数BMI:对身体质量的刻画(Body Mass Index)
国际上常用的衡量人体肥胖和健康程度的重要标准,主要用于统计分析
定义:
BMI=体重(kg)/身高^2(m2)
提出问题:
实例:体重72kg 身高1.75m
BMI值是23.5
这个值是否健康呢?
分类 | 国际BMI值(kg/m^2) | 国内BMI值(kg/m^2) |
偏瘦 | <18.5 | <18.5 |
正常 | 18.5-25 | 18.5-24 |
偏胖 | 25-30 | 24-28 |
肥胖 | >=30 | >=28 |
问题分析:
1、输入:给定体重和身高值
2、输出:BMI指标分类信息(国际和国内)
我们大概有两个思路:
思路1:分别计算给出国际和国内的BMI分类
思路2:混合计算并给出国际国内BMI分类
首先我们根据思路一编写如下代码
1 #CalBMIv1.py 2 height, weight = eval(input("请输入身高(米)和体重(公斤)[逗号隔开]: ")) 3 bmi = weight / pow(height, 2) 4 print("BMI 数值为:{:.2f}".format(bmi)) 5 who = "" 6 if bmi < 18.5: 7 who = "偏瘦" 8 elif 18.5 <= bmi < 25: 9 who = "正常" 10 elif 25 <= bmi < 30: 11 who = "偏胖" 12 else: 13 who = "肥胖" 14 print("BMI 指标为:国际'{0}'".format(who))
1 #CalBMIv2.py 2 height, weight = eval(input("请输入身高(米)和体重\(公斤)[逗号隔开]: ")) 3 bmi = weight / pow(height, 2) 4 print("BMI 数值为:{:.2f}".format(bmi)) 5 nat = "" 6 if bmi < 18.5: 7 nat = "偏瘦" 8 elif 18.5 <= bmi < 24: 9 nat = "正常" 10 elif 24 <= bmi < 28: 11 nat = "偏胖" 12 else: 13 nat = "肥胖" 14 print("BMI 指标为:国内'{0}'".format(nat))
根据思路2,可以编写如下程序
1 #CalBMIv3.py 2 height, weight = eval(input("请输入身高(米)和体重(公斤)[逗号隔开]: ")) 3 bmi = weight / pow(height, 2) 4 print("BMI 数值为:{:.2f}".format(bmi)) 5 who, nat = "", "" 6 if bmi < 18.5: 7 who, nat = "偏瘦", "偏瘦" 8 elif 18.5 <= bmi < 24: 9 who, nat = "正常", "正常" 10 elif 24 <= bmi < 25: 11 who, nat = "正常", "偏胖" 12 elif 25 <= bmi < 28: 13 who, nat = "偏胖", "偏胖" 14 elif 28 <= bmi < 30: 15 who, nat = "偏胖", "肥胖" 16 else: 17 who, nat = "肥胖", "肥胖" 18 print("BMI 指标为:国际'{0}', 国内'{1}'".format(who, nat))
大家可以动手试试