Chaco MultiplePlot无法显示简单绘图，想知道包是否损坏？

Question

我正在尝试创建一个多线图来显示来自2dnumpy数组的多个时间序列数据（电压）。我已经开始非常简单地尝试从2x10数组绘制两条线和十个数据点，但是如果没有大量的错误输出（我无法调试），我甚至无法使其工作。在

进口：

import numpy
from traits.api import HasTraits, Instance
from traitsui.api import View, Item
from chaco.api import MultiLinePlot, ArrayDataSource, MultiArrayDataSource
from enable.component_editor import ComponentEditor

测试阵列：

^{pr2}$

显示类：

class Multi_line_graph(HasTraits):

    plot = Instance(MultiLinePlot)

    traits_view = View(
    Item('plot',editor=ComponentEditor(), show_label=False),
    width=1024, height=768, resizable=True, title="EEG Preview")

    def __init__(self, my_data):
        super(Multi_line_graph, self).__init__()

        x = ArrayDataSource(numpy.arange(1, my_data.shape[0]))

        y = my_data.transpose()   #since my data columnwise
        y = MultiArrayDataSource(y)

        yidx = ArrayDataSource(numpy.arange(y.get_shape()[0]))

        plot = MultiLinePlot(index=x, yindex=yidx, value=y)

        self.plot = plot

创建类的实例：

my_graph = Multi_line_graph(test_array)

显示（配置特征）：

my_graph.configure_traits()

然后我看到一个窗口出现，但是它挂起并使Python内核崩溃，shell中显示了这个错误：

Exception occurred in traits notification handler for object: <chaco.multi_line_plot.MultiLinePlot object at 0x000000000D0CFD58>, trait: bounds_items, old value: <undefined>, new value: <traits.trait_handlers.TraitListEvent object at 0x000000000D18C908>
Traceback (most recent call last):
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\traits\trait_notifiers.py", line 340, in __call__
self.handler( *args )
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\chaco\base_xy_plot.py", line 613, in _bounds_items_changed
self._update_mappers()
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\chaco\base_xy_plot.py", line 594, in _update_mappers
x_mapper.screen_bounds = (x, x2)
AttributeError: 'NoneType' object has no attribute 'screen_bounds'
Exception occurred in traits notification handler for object: <chaco.multi_line_plot.MultiLinePlot object at 0x000000000D0CFD58>, trait: bounds_items, old value: <undefined>, new value: <traits.trait_handlers.TraitListEvent object at 0x000000000D0C4C88>
Traceback (most recent call last):
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\traits\trait_notifiers.py", line 340, in __call__
self.handler( *args )
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\chaco\base_xy_plot.py", line 613, in _bounds_items_changed
self._update_mappers()
File "C:\Users\pzl46097\AppData\Local\Enthought\Canopy\User\lib\site-packages\chaco\base_xy_plot.py", line 594, in _update_mappers
x_mapper.screen_bounds = (x, x2)
AttributeError: 'NoneType' object has no attribute 'screen_bounds'
Exception occurred in traits notification handler.
Please check the log file for details.

我真的不知道这意味着什么。我已经阅读并重新阅读了API文档：

http://docs.enthought.com/chaco/api/renderers.html#multilineplot

以及用户指南文档：

http://docs.enthought.com/chaco/user_manual/plot_types.html#multi-line-plot

但似乎没有任何关于这个类的其他文档。我想知道它是不是没有维护，可能是坏了，或者是我做错了什么（我很可能是因为我只使用了Chaco大约一个星期，库对我来说是新的，就像Python中的OOP一样）。在

非常感谢您的帮助。。在

Answer 1

不知道您在镜像哪个示例，但是直接使用数据源实例并不是从Chaco开始的最简单方法。在

我的建议是使用常规的Plot类和ArrayPlotData类来存储数组。展开一点，假设您要绘制多个时间序列，下面是一个使用不同颜色的多个线条图的工作示例：

import numpy 
from traits.api import Array, HasTraits, Instance 
from traitsui.api import View, Item 
from chaco.api import ArrayPlotData, Plot 
from enable.api import ComponentEditor

test_array = numpy.random.rand(10, 2)    

class Multi_line_graph(HasTraits):

    plot = Instance(Plot)

    data = Array

    traits_view = View(
        Item('plot', editor=ComponentEditor(), show_label=False),
        width=1024, height=768, resizable=True, title="EEG Preview"
    )

    def _plot_default(self):
        data = {"x": t_array[0, :], "y1": t_array[1, :], "y2": t_array[2, :]}
        plot = Plot(ArrayPlotData(**data))
        plot.plot(("x", "y1"), type="line", color="blue")
        plot.plot(("x", "y2"), type="line", color="red")
        return plot

my_graph = Multi_line_graph(data=test_array)
my_graph.configure_traits()