如何在Django中使用Matplotlib？

From some examples from the Internet I made the test code below. It works!

从互联网上的一些例子中我制作了下面的测试代码。有用！

... BUT if I reload the page, the pie will draw itself with the same image. Some parts get darker every time I reload the page. When I restart the the development server, it is reset. How do I draw properly with Matplotlib in Django? It looks like it remembers some drawings...

...但是，如果我重新加载页面，饼图将使用相同的图像绘制自己。每次重新加载页面时，某些部分会变暗。当我重新启动开发服务器时，它会被重置。如何在Django中使用Matplotlib正确绘制？它看起来好像记得一些图纸......

Source views.py (let urls.py link to it):

源views.py（让urls.py链接到它）：

from pylab import figure, axes, pie, title
from matplotlib.backends.backend_agg import FigureCanvasAgg

def test_matplotlib(request):
    f = figure(1, figsize=(6,6))
    ax = axes([0.1, 0.1, 0.8, 0.8])
    labels = 'Frogs', 'Hogs', 'Dogs', 'Logs'
    fracs = [15,30,45, 10]
    explode=(0, 0.05, 0, 0)
    pie(fracs, explode=explode, labels=labels, autopct='%1.1f%%', shadow=True)
    title('Raining Hogs and Dogs', bbox={'facecolor':'0.8', 'pad':5})

    canvas = FigureCanvasAgg(f)    
    response = HttpResponse(content_type='image/png')
    canvas.print_png(response)
    return response

I am using Django 1.0.1 and Python 2.6.2 (Linux).

我正在使用Django 1.0.1和Python 2.6.2（Linux）。

1 个解决方案

#1

You need to remove the num parameter from the figure constructor and close the figure when you're done with it.

您需要从图形构造函数中删除num参数，并在完成后关闭图形。

import matplotlib.pyplot

def test_matplotlib(request):
    f = figure(figsize=(6,6))
    ....
    matplotlib.pyplot.close(f)

By removing the num parameter, you'll avoid using the same figure at the same time. This could happen if 2 browsers request the image at the same time. If this is not an issue, another possible solution is to use the clear method, i.e. f.clear().

通过删除num参数，您将避免同时使用相同的数字。如果2个浏览器同时请求图像，则可能发生这种情况。如果这不是问题，另一种可能的解决方案是使用clear方法，即f.clear（）。