如何计算每个年龄段的人数（Django）

我有

这个函数呢

class Person(TimeStampedModel, Address):
    name = models.CharField(_('nome'), max_length=100)
    birthday = models.DateField(_('data de nascimento'))

---

我知道我必须使用annotate和count，但不知道从哪里开始。

在您的情况下，我将使用两个函数，一个用于获取人员的年龄，另一个用于准备一个dict，返回按年龄范围分组的人员

age quant
20-25   89
25-30   100
30-35   90
35-40   102

因此，当您拥有person对象时，您可以执行以下操作：

class Person(TimeStampedModel, Address):
    name = models.CharField(_('nome'), max_length=100)
    birthday = models.DateField(_('data de nascimento'))

    def calculate_age(self):
        today = date.today()
        born = self.birthday
        return today.year - born.year - ((today.month, today.day) < (born.month, born.day))

---

回报将是以年为单位的年龄

这里的几个答案将帮助您：

def calculate_age(born):
    today = date.today()
    return today.year - born.year - ((today.month, today.day) < (born.month, born.day))

def get_persons_grouped_by_age():
    age_dict = {
        "under_20": [],
        "20_25": [],
        "25_30": [],
        "30_35": [],
        "35_40": [],
        "over_40": [],
    }

    for person in Person.objects.all():
        person_age = calculate_age(person.birthday)
        if person_age < 20:
           age_dict["under_20"].append(person)
        if 20 <= person_age < 25:
           age_dict["20_25"].append(person)
        elif 25 <= person_age < 30:
           age_dict["25_30"].append(person)
        elif 30 <= person_age < 35:
           age_dict["30_35"].append(person)
        elif 35 <= person_age < 40:
           age_dict["35_40"].append(person)
        else:
           age_dict["over_40"].append(person)

    return age_dict

class Person(TimeStampedModel, Address):
    name = models.CharField(_('nome'), max_length=100)
    birthday = models.DateField(_('data de nascimento'))

    def calculate_age(self):
        today = date.today()
        born = self.birthday
        return today.year - born.year - ((today.month, today.day) < (born.month, born.day))

person.calculate_age()