小编Hag*_*zel的帖子

我尝试使用matplotlib在python上绘制图形,但我不能得到预期的结果.

公式1: 1/2 * (w1 + w2) + 1/2 * np.sqrt(4*(g)**2 + (w2-w1)**2)

公式2: 1/2 * (w1 + w2) - 1/2 * np.sqrt(4*(g)**2 + (w2-w1)**2)

我的python代码:

import matplotlib.pyplot as plt
import numpy as np

def W_p(w1,w2,g):
   return 1/2 * (w1 + w2) + 1/2 * np.sqrt(4*(g)**2 + (w2-w1)**2)

def W_m(w1,w2,g):
    return 1/2 * (w1 + w2) - 1/2 * np.sqrt(4*(g)**2 + (w2-w1)**2)

w1 = np.linspace(-10,10,1)
w2 = np.linspace(0.9,1.10,0.1)
g = 1

plt.plot(W_p(w1,w2,g), 'r', W_m(w1,w2,g), 'b')

plt.show()

generatad图应该如下图所示:

我是 django 新手，我尝试修改一个项目来学习。

我的模型中有两个类（“Order”和“OrderItem”），OrderItem 类存储客户订单中选择的所有项目。

模型.py

class Order(models.Model):

    STATUS_CHOICES = (
        (0, 'Waiting Payment'),
        (1, 'Completed'),
        (2, 'Canceled'),
    )

    PAYMENT_OPTION_CHOICES = (
        ('deposit', 'deposit'),
        ('paypal', 'Paypal'),
    )

    user = models.ForeignKey(settings.AUTH_USER_MODEL, verbose_name='User')
    status = models.IntegerField(
        'Situation', choices=STATUS_CHOICES, default=0, blank=True
    )
    payment_option = models.CharField(
        'Payment Options', choices=PAYMENT_OPTION_CHOICES, max_length=20,
         default='deposit'
    )

    created = models.DateTimeField('Created in', auto_now_add=True)
    modified = models.DateTimeField('Modified in', auto_now=True)

    objects = OrderManager()

    class Meta:
        verbose_name = 'Order'
        ordering = ('-created',)

    def __str__(self):
        return 'Order #{}'.format(self.pk)

    def products(self):
        products_ids = self.items.values_list('product')
        return …