Question

我的问题是：我在PyGTK应用程序中有Matplotlib图，每隔几秒就会进行一次更新。我添加了将数据保存为磁盘的能力，如PNG文件。调用figure.savefig(filename, other parameters)后，我的应用程序中的数字停止更新。

图初始化阶段：

# setup matplotlib stuff on empty space in vbox4
    figure = Figure()
    canvas = FigureCanvasGTK(figure) # a gtk.DrawingArea
    canvas.show()
    self.win.get_widget('vbox4').pack_start(canvas, True, True) # this will be aded to last place
    self.win.get_widget('vbox4').reorder_child(canvas, 1) #place plot to space where it should be

图正在以这种方式更新（这在单独的线程中每隔几秒调用一次）：

def _updateGraph(self, fig, x, x1, y):
    #Various calculations done here

    fig.clf()#repaint plot: delete current and formate a new one
    axis = fig.add_subplot(111)
    #axis.set_axis_off()
    axis.grid(True)
#remove ticks and labels
    axis.get_xaxis().set_ticks_position("none")
    for i in range(len(axis.get_xticklabels())): axis.get_xticklabels()[i].set_visible(False)
    axis.get_yaxis().set_ticks_position("none")
    axis.plot(numpy.array(x),numpy.array(y)/(1.0**1), "k-" ,alpha=.2)
    axis.set_title('myTitle')
    fig.autofmt_xdate()
    fig.canvas.draw()

一切都按预期工作。但是在打电话之后：

figure.savefig(fileName, bbox_inches='tight', pad_inches=0.05)

文件已保存，但屏幕上的数字不再更新。

任何想法如何将数字保存到磁盘并仍然可以在屏幕上更新我的图形？

Answer 1

您是否尝试过更新行数据而不是重新创建数字？这假设数据点的数量不会改变每一帧。它可能有助于解决拒绝更新的问题，至少它会更快。

def _updateGraph(self, fig, x, x1, y): 
    #Various calculations done here 


    ydata = numpy.array(y)/(1.0**1)

    # retrieved the saved line object
    line = getattr(fig, 'animated_line', None);

    if line is None:
        # no line object so create the subplot and axis and all 
        fig.clf()
        axis = fig.add_subplot(111) 

        axis.grid(True) 
        #remove ticks and labels 
        axis.get_xaxis().set_ticks_position("none") 
        for i in range(len(axis.get_xticklabels())): 
            axis.get_xticklabels()[i].set_visible(False) 
        axis.get_yaxis().set_ticks_position("none")             
        xdata = numpy.array(x);
        line = axis.plot(xdata, ydata, "k-" ,alpha=.2) 
        axis.set_title('myTitle') 
        fig.autofmt_xdate() 

        # save the line for later reuse
        fig.animated_line = line
    else:
        line.set_ydata(ydata)
    fig.canvas.draw()

Answer 2

我找到了一个圆满的工作。因为我的数字在调用figure.savefig()之后拒绝更新，所以我找到了一种方法来解决它。我的数字在HBox2容器内（GUI是用Glade 3.6.7创建的）作为第一个元素

#   some stuff going
    figure.saveFig(fileName)
#   WORK-A-ROUND: delete figure after calling savefig()
    box = self.win.get_widget('hbox2')
    box.remove(box.get_children()[0])
    self._figPrepare()

def _figPrepare(self):  #initialize graph
    figure = Figure()
    canvas = FigureCanvasGTK(figure) # a gtk.DrawingArea
    canvas.show()       
    figure.clf()
    gui.w().set("figure", figure)
    self.win.get_widget('hbox2').pack_start(canvas, True, True) # this will be aded to last place
    self.win.get_widget('hbox2').reorder_child(canvas, 0) #place plot to space where it should be

我知道这不是最佳做法，可能很慢，但对我来说还可以。希望别人能找到这个有用的

Answer 3

来自http://matplotlib.org/examples/user_interfaces/embedding_in_gtk2.html

似乎有帮助的是“agg”不确定这意味着什么，但为我修复了这个错误：）

from matplotlib.backends.backend_gtkagg import FigureCanvasGTKAgg as FigureCanvas

Python matplotlib在savefig调用后更新图

3 个答案: