使用FigureCanvasQTAgg时,不同的DataFrame绘制行为

Question

我正在尝试创建一个包含在pandas DataFrame中的几个数据系列的图.我们df以一个例子为例:

import pandas as pd
import matplotlib.pyplot as plt

d = {'1': [1,2,3], '2': [1,4,9]}
df = pd.DataFrame(d)
df.plot()
plt.show()

此代码生成一个包含两个不同数据系列的简单折线图:

但是,如果我尝试使用PyQt小部件创建相同的绘图FigureCanvasQTAgg,我只会得到一行.我的第二个例子的代码更多涉及:

import pandas as pd
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
from PyQt4.QtGui import QWidget, QSizePolicy, QApplication

class DisplayWidget( QWidget ):
    def __init__(self, parent=None):
        super( DisplayWidget, self).__init__( parent )

        self.initUI()

        d = {'1': [1,2,3], '2': [1,4,9]}        
        self.df = pd.DataFrame(d)
        self.canvas.plot_data_frame(self.df)

    def initUI(self):

        self.canvas = PlotCanvas(self)

class PlotCanvas(FigureCanvas):
    def __init__(self, parent=None, width=5, height=4, dpi=100):
        self.fig = Figure(figsize=(width, height), dpi=dpi)
        self.axes = self.fig.add_subplot(111)
        self.axes.hold(False)

        FigureCanvas.__init__(self, self.fig)
        self.setParent(parent)

        FigureCanvas.setSizePolicy(self,
                                   QSizePolicy.Expanding,
                                   QSizePolicy.Expanding)
        FigureCanvas.updateGeometry(self)


    def plot_data_frame( self, df, **kwargs ):
        df.plot( ax = self.axes, **kwargs )
        self.draw()        

if __name__ == "__main__":

    app = QApplication( [] )
    widget = DisplayWidget()
    widget.show()
    app.exec_()

当我运行此代码时,输​​出如下所示:

如果有人能够对此有所了解,那将非常感激!

谢谢.

Answer 1

删除此行:

self.axes.hold(False)