Question

我正在创建一个网页，显示我使用Django在matplotlib中创建的图形。该脚本本身运行良好，但由于某种原因它在Django中不起作用。

这是我得到的错误：

This call to matplotlib.use() has no effect
because the backend has already been chosen;
matplotlib.use() must be called *before* pylab, matplotlib.pyplot,
or matplotlib.backends is imported for the first time.

我在第一行导入matplotlib.use（），如下所示：

import matplotlib
matplotlib.use('TkAgg')

from django.shortcuts import render
from django.http import HttpResponse
from pylab import figure, axes, pie, title

我使用matplotlib.use（＆＃39; TkAgg）来解决我在Django中没有脚本时遇到的问题。我认为同样的解决方案可以在Django中运行，但它给了我一个错误。有人知道如何修复代码吗？

我的代码很长，所以我只提供它的代码片段。我的函数名称非常具有描述性，所以我认为您能够直观地理解一些函数（这是我的views.py文件）：

def index(request):
    noaaNmbr='11809'
    #for right now, this is the only active region that I'm pulling data for. When I get the graph up and running, I will make it more interactive for the user so that he can 

    urlData = "http://www.lmsal.com/hek/hcr?cmd=search-events3&outputformat=json&instrument=IRIS&noaanum="+ noaaNmbr +"&hasData=true"

    webUrl = urlopen(urlData)
    counter = 0
    data = webUrl.read().decode('utf-8')
    hekJSON = json.loads(data)
    getInfo(counter, hekJSON)

    sort()
    # Sorts the data from earliest to most recent

    fig, ax = plt.subplots(figsize=(30, 30))
    circle = Circle((0, 0), 980, facecolor='none', edgecolor=(0, 0.8, 0.8), linewidth=3, alpha=0.5)
    ax.add_patch(circle)
# Creates circular representation of the sun on the graph because that's all I really need for now

    plt.plot(xcen, ycen, color="red")
    plt.plot(xcen, ycen, 'ro', color = 'blue')
    #first plots the points in red, then draws lines between the points in blue

    plt.xlim([setXMin(hekJSON), setXMax(hekJSON)])
    plt.ylim([setYMin(hekJSON), setYMax(hekJSON)])
#sets the boundaries of the graph

    ax.set_xticks(np.arange(setXMin(hekJSON), setXMax(hekJSON), 50))
    ax.set_yticks(np.arange(setYMin(hekJSON), setYMax(hekJSON), 50))
#sets the ticks

    for i in range(getNumberOfEntries(hekJSON)):
        if xfov[i] != 0:
            xStart = xcen[i] - xfov[i]/14
            yStart = ycen[i] - yfov[i]/14
            ax.add_patch(Rectangle((xStart, yStart), xfov[i]/7, yfov[i]/7, facecolor='none'))

    plt.grid()

    texts = fixAnnotations(createAnnotations(hekJSON, noaaNmbr))
    adjust_text(texts, arrowprops=dict(arrowstyle="-", color='k', lw=0.5))

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

如何使用Django更改Matplotlib中的后端？

0 个答案: