使用for循环简化重复乘法？

Question

有没有更优雅的方法来编写这段代码？我一遍又一遍地做着同样的手术，所以感觉好像有，但我想不起来

成人是一个数据框架。体重是人的样本体重，每个ped变量代表不同的残疾类型

total_cognitive_m = (adults.weight * (adults.pedisrem==1)).sum()/1e6
total_mobility_m = (adults.weight * (adults.pedisout==1)).sum()/1e6
total_self_care_m = (adults.weight * (adults.pedisdrs==1)).sum()/1e6
total_physical_m = (adults.weight * (adults.pedisphy==1)).sum()/1e6 
total_vision_m = (adults.weight * (adults.pediseye==1)).sum()/1e6
total_hearing_m = (adults.weight* (adults.pedisear==1)).sum()/1e6
total_disabled_m = (adults.weight * adults.disabled).sum()/1e6

Answer 1

这段代码假设属性总是在变量上

'''
The common behaviour of picking an attribute on adult 
like pedisrem and doing ( adult.weights * <attribute of adults> == 1).sum()/1e6
has been achieved using list comprehension, we store those attributes
in equalsToOne array and iterate over them.

'''

multiplier = 'weight'
equalsToOne = ['pedisrem', 'pedisout', 'pedisdrs', 'pedisphy', 'pediseye', 'pedisear']
total_cognitive_m, total_mobility_m, total_self_care_m, \
 total_physical_m, total_vision_m, total_hearing_m = 
[(getattr(adults, multiplier) * getattr(adults, var) == 1).sum()/1e6
 for var in equalsToOne]
total_disabled_m = (adults.weight * adults.disabled).sum()/1e6

Answer 2

如果您可以创建一个函数来减少重复代码，这将有所帮助：

def calc(adults, name):
    return (adults.weight * (getattr(adults,name)==1)).sum() / 1e6

但是，如果您使用的是多个单独的变量，那么每个变量都必须有一个单独的赋值语句（不包括某些高级但“黑客”的解决方案）：

total_cognitive_m = calc(adults, 'pedisrem')
total_mobility_m = calc(adults, 'pedisout')
... etc ...

如果您可以将输出数据放入某种集合，例如字典，则效果更好。在这种情况下，您可以执行以下操作，例如：

inputs_to_use = {
    'total_cognitive_m': 'pedisrem',
    'total_mobility_m': 'pedisout',
    ... etc ...
    }

然后，您可以使用以下工具创建输出词典：

outputs = { key: calc(adults, name) 
            for key, name in inputs_to_use.items() }

然后查找值，例如通过执行

print(outputs["total_cognitive_m"])

Answer 3

您可以定义一些集合来迭代数据，您可以使用元组来声明每个项目属性成人.pedisrem，成人.pedisout，成人.pedisdrs，…，然后使用数组存储每个结果

properties = ("pedisrem","pedisout","pedisdrs")
totalValues = ("total_cognitive_m","total_mobility_m","total_self_care_m")
relationShip = {}
i = 0
for item in properties:
    relationShip[totalValues[i]]  = (adults.weight * (adults[item]==1)).sum()/1e6
    i = i + 1;

print(relationShip);