Question

我在

中有以下型号

from django.db import models

# Create your models here.

class Post(models.Model):
    text = models.TextField()

    def __str__(self):
        return self.text[:50]


POWER_CHOICES= (('O', 'ON'),
                ('F','OFF')
        )

STATE_CHOICES =(('AV','Available'),
               ('U','In Use '),
               ('NU','Do Not Use')                
       )

class Device(models.Model):

   name = models.CharField(unique=True,max_length=50 )

   ipaddress=models.ForeignKey('Ipaddress', on_delete=models.CASCADE,)

   devicetype= models.ForeignKey('DeviceType', on_delete=models.CASCADE)
   model= models.ForeignKey('DeviceModel', on_delete=models.CASCADE)
   description= models.TextField(max_length=400)
   location= models.ForeignKey('Location', on_delete=models.CASCADE)
   group= models.ForeignKey('DeviceGroup', on_delete=models.CASCADE)
   managment= models.CharField(max_length=100)
   power= models.CharField(max_length=6, choices=POWER_CHOICES)
   offtime= models.CharField(max_length=30)
   state= models.CharField(max_length=10, choices=STATE_CHOICES)
   user= models.CharField(max_length=100)
#   department= models.ForeignKey('Department',on_delete=models.CASCADE)
   comments= models.CharField(max_length=200)

   def __unicode__(self):
        return self.name[:50]

class DeviceType(models.Model):
    name= models.CharField(max_length=100, unique=True)

    def __unicode__(self):
        return self.name[:50]

class DeviceModel(models.Model):
    name= models.CharField(max_length=100, unique=True)

    def __unicode__(self):
        return self.name[:50]

class Ipaddress(models.Model):
    address=models.CharField(max_length=20, unique=True)
    owner=models.CharField(max_length=200)
    loation=models.CharField(max_length=200)
    note =models.TextField()
    def __unicode__(self):
        return self.address[:50]

class Department:
    name= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.name[:50] 


class DeviceGroup:
    name= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.name[:50] 

class Location:
    description= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.description[:50]

我的管理页面如下所示：

from django.contrib import admin
from pages.models import Post, Device, DeviceType, DeviceModel, Ipaddress, DeviceGroup, Location

admin.site.register(Post)
admin.site.register(Device)
admin.site.register(DeviceType)
admin.site.register(DeviceModel)
admin.site.register(Ipaddress)
#admin.site.register(Department)
admin.site.register(DeviceGroup)
admin.site.register(Location)

我看到以下错误，不确定是什么原因导致此错误。有人可以给我一些想法吗？请

...
...
File "C:\Users\mohiuddin_rana\labmcproject\pages\admin.py", line 10, in <module>
    admin.site.register(DeviceGroup)
  File "C:\Users\mohiuddin_rana\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\contrib\admin\sites.py", line 102, in register
    for model in model_or_iterable:
TypeError: 'type' object is not iterable

Answer 1

对于某些模型，您忘记了从models.Model继承它：

class Department(models.Model):
    name= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.name[:50] 


class DeviceGroup(models.Model):
    name= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.name[:50] 

class Location(models.Model):
    description= models.CharField(max_length=100, unique=True)
    def __unicode__(self):
        return self.description[:50]

此更改还将导致一些迁移，因为到目前为止，Django（可能）还不了解这些类实际上是模型，因此不是构造数据库等效项。

在将模型注册到admin.site变量时，Django需要一个模型，但是检查失败。作为一种“后备”机制，它检查您是否提供了可迭代的模型，但这又失败了，因为它只是一个“香草”类。

当我们检查source code of the register(..) function [GitHub]时，可以确认此行为：

def register(self, model_or_iterable, admin_class=None, **options):

    # ...

    admin_class = admin_class or ModelAdmin
    if isinstance(model_or_iterable, ModelBase):
        model_or_iterable = [model_or_iterable]
    for model in model_or_iterable:
        # ...
        pass

（我删除了一些部分以使语义更清晰）。

如您所见，它将检查您传递的model_or_iterable是否为模型。如果是这种情况，它将把它包装在一个列表中，否则就假定它是可迭代的，并旨在对其进行迭代。

注意：您似乎使用__unicode__，但同时使用Python-3.x。据我所知，__unicode__在Python-3.x数据模型中不再具有任何意义。您应该改用__str__。

Answer 2

set.seed(1680)

library(dplyr) 
library(ISLR) 
library(cluster) 

college_clean <- College %>%
  mutate(name = row.names(.),
         accept_rate = Accept/Apps,
         isElite = cut(Top10perc,
                       breaks = c(0, 50, 100),
                       labels = c("Not Elite", "Elite"),
                       include.lowest = TRUE)) %>%
  mutate(isElite = factor(isElite)) %>%
  select(name, accept_rate, Outstate, Enroll,
         Grad.Rate, Private, isElite)



gower_dist <- daisy(college_clean[,-1],
                    metric = "gower",
                    type = list(logratio = 3))
pam_fit <- pam(gower_dist, diss = TRUE, k = 3)


newdf=data.frame(name=c("x_university","y_university","z_university"),
                accept_rate=c(.73,.50,.98),Outstate=c(10000,15000,5000),
                Enroll=c(500,1000,200),Grad.Rate=c(80,65,73),
                Private=c("Yes","No","No"),isElite=c("Elite","Not Elite", "Elite"))

将（models.Model）包含在您的所有班级中

在model_or_iterable中看到模型的错误寄存器：TypeError：'type'对象不可迭代

2 个答案: