Question

我有一个轨迹列表（各种长度），我想要（重叠）在同一张图中绘制，然后显示/保存它。这可以通过运行一个简单的for循环并为每个轨迹调用plt.plot()，最后运行plt.show()来完成。

（使用import matplotlib.pyplot as plt）

这对于许多轨迹（> 10k）来说非常慢，所以我想并行化这些图，但最后仍然只有一个图。

我发现有几个posts实现了这一目标，但是在每个过程中都进行了绘制。但是，这不是我所需要的，因为所有轨迹都必须在一个图中。

我还尝试过以下方法：


import matplotlib.pyplot as plt
import multiprocessing as mpi

class WorkerClass():
    def __init__(self, ax):
        self.ax = ax

    def worker(self, tli):
        t,l,i = tli
        self.ax.plot(t[:,0], t[:,1], alpha=0.5, color='C0' if l==-1 else 'C1', linestyle=np.array(['-','-.',':','--',':'])[i.astype(bool)][0])

    def get_ax(self):
        return self.ax


### main code
# trajectories, labels, info are lists passed from other functions

fig, ax = plt.subplots()
w = Worker(ax)

with mpi.Pool(processes=4) as p:
        lines = p.map(w.worker, zip(trajectories, labels, info))

ax = w.get_ax()
ax.set_title('Trajectories')
plt.show()

但是这不起作用，我得到一个堆栈错误：

Exception in thread Thread-3:
Traceback (most recent call last):
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/threading.py", line 914, in _bootstrap_inner
    self.run()
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/threading.py", line 862, in run
    self._target(*self._args, **self._kwargs)
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/multiprocessing/pool.py", line 429, in _handle_results
    task = get()
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/multiprocessing/connection.py", line 251, in recv
    return ForkingPickler.loads(buf.getbuffer())
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/site-packages/matplotlib/figure.py", line 1904, in __setstate__
    mgr = plt._backend_mod.new_figure_manager_given_figure(num, self)
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/site-packages/matplotlib/backends/_backend_tk.py", line 1044, in new_figure_manager_given_figure
    window = Tk.Tk(className="matplotlib")
  File "/home/robin/anaconda3/envs/py35lab/lib/python3.5/tkinter/__init__.py", line 1868, in __init__
    self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)
_tkinter.TclError: out of stack space (infinite loop?)

多进程线生成，但在主图中绘制

0 个答案: