python
Traceback (most recent call last):
File "E:\workspace\python_project\aitest\test1.py", line 20, in <module>
do_test()
File "E:\workspace\python_project\aitest\test1.py", line 15, in do_test
plt.plot(x, y, 'r-', linewidth=3)
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 3575, in plot
return gca().plot(
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 2525, in gca
return gcf().gca()
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 1000, in gcf
return figure()
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 934, in figure
manager = new_figure_manager(
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 464, in new_figure_manager
_warn_if_gui_out_of_main_thread()
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 441, in _warn_if_gui_out_of_main_thread
canvas_class = cast(type[FigureCanvasBase], _get_backend_mod().FigureCanvas)
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 280, in _get_backend_mod
switch_backend(rcParams._get("backend")) # type: ignore[attr-defined]
File "E:\workspace\python_project\aitest\venv\lib\site-packages\matplotlib\pyplot.py", line 343, in switch_backend
canvas_class = module.FigureCanvas
AttributeError: module 'backend_interagg' has no attribute 'FigureCanvas'. Did you mean: 'FigureCanvasAgg'?
问题原因
从问题中可以看到 :module 是设置成 backend_interagg 即 backend 是 agg
从源码中,我们可以看到,matplotlib.pylot 的默认 backend 是设置成agg的

python
global _backend_mod
# make sure the init is pulled up so we can assign to it later
import matplotlib.backends
if newbackend is rcsetup._auto_backend_sentinel:
current_framework = cbook._get_running_interactive_framework()
mapping = {'qt': 'qtagg',
'gtk3': 'gtk3agg',
'gtk4': 'gtk4agg',
'wx': 'wxagg',
'tk': 'tkagg',
'macosx': 'macosx',
'headless': 'agg'}
if current_framework in mapping:
candidates = [mapping[current_framework]]
else:
candidates = []
candidates += [
"macosx", "qtagg", "gtk4agg", "gtk3agg", "tkagg", "wxagg"]
# Don't try to fallback on the cairo-based backends as they each have
# an additional dependency (pycairo) over the agg-based backend, and
# are of worse quality.
for candidate in candidates:
try:
switch_backend(candidate)
except ImportError:
continue
else:
rcParamsOrig['backend'] = candidate
return
else:
# Switching to Agg should always succeed; if it doesn't, let the
# exception propagate out.
switch_backend("agg")
rcParamsOrig["backend"] = "agg"
return
解决方案
1、安装matplotlib3.5.0及以下版本
python
pip install matplotlib==3.5.0
2、指定后端TkAgg
import matplotlib
matplotlib.use('TkAgg')
拓展
一次性显示多个图
plt.figure()
#figure1代码
plt.figure()
#figure2代码
#......
plt.show()
#只需要每张图前加入figure(),最后加show()即可
多条曲线绘制在一张图
plt.figure()
plt.plot(x1,y1)
plt.plot(x2,y2)
#......
plt.show()
#一个figure()+一个show()
一次只弹出一个独立窗口
#figure1
plt.figure()
plt.show()
#figure2
plt.figure()
plt.show()
#程序会一直等待手动关闭一个窗口后再继续运行代码