1 #_*_coding:utf-8_*_ 2 ‘‘‘ 3 Created on 2014年12月10日 4  5 @author: Administrator 6 ‘‘‘ 7 from PyQt4.QtCore import * 8 from PyQt4.QtGui import * 9 from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvas10 from matplotlib.figure import Figure11 import matplotlib.pyplot as plt12 import sys13 14 class DrawWidget(QWidget):15     def __init__(self,parent=None):16         super(DrawWidget,self).__init__(parent)17         18         figure = plt.gcf() #返回当前的figure19         self.canvas = figureCanvas(figure)20         x = [1,2,3]21         y = [4,5,6]22         plt.plot(x,y)23         plt.title(‘Example‘)24         plt.xlabel(‘x‘)25         plt.ylabel(‘y‘)26         self.canvas.draw()27         layout = QHBoxLayout(self)28         layout.addWidget(self.canvas)29         30     31 if __name__ == ‘__main__‘:32     app = QApplication(sys.argv)33     ui = DrawWidget()34     ui.show()35     app.exec_()

 1 #_*_coding:utf-8_*_ 2 ‘‘‘ 3 Created on 2014年12月10日 4  5 @author: Administrator 6 ‘‘‘ 7 from PyQt4.QtCore import * 8 from PyQt4.QtGui import * 9 from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvas10 import matplotlib.pyplot as plt11 import sys12 13 class Example1(QWidget):14     def __init__(self,parent=None):15         super(Example1,self).__init__(parent)16         17         figure = plt.gcf() #返回当前的figure18         self.canvas = figureCanvas(figure)19         x = [1,2,3]20         y = [4,5,6]21         plt.plot(x,y)22         plt.title(‘Example‘)23         plt.xlabel(‘x‘)24         plt.ylabel(‘y‘)25         self.canvas.draw()26         layout = QHBoxLayout(self)27         layout.addWidget(self.canvas)28         29 class Example2(QWidget):30     def __init__(self,parent=None):31         super(Example2,self).__init__(parent)32         33         figure1 = plt.figure(1) #返回当前的figure34         x = [1,2,3]35         y = [4,5,6]36         plt.plot(x,y)37         plt.title(‘Example1‘)38         plt.xlabel(‘x‘)39         plt.ylabel(‘y‘)40         41         figure2 = plt.figure(2) #返回当前的figure42         x = [7,8,9]43         y = [4,5,6]44         plt.plot(x,y)45         plt.title(‘Example2‘)46         plt.xlabel(‘x‘)47         plt.ylabel(‘y‘)48         49         self.canvas1 = figureCanvas(figure1)50         self.canvas2 = figureCanvas(figure2)51         self.canvas1.draw()52         self.canvas2.draw()53         layout = QHBoxLayout(self)54         layout.addWidget(self.canvas1)55         layout.addWidget(self.canvas2)56         57     58 if __name__ == ‘__main__‘:59     app = QApplication(sys.argv)60     ui = Example2()61     ui.show()62     app.exec_()

#_*_coding:utf-8_*_‘‘‘Created on 2014年12月10日@author: Administrator‘‘‘from PyQt4.QtCore import *from PyQt4.QtGui import *from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvasimport matplotlib.pyplot as pltimport sysclass Example1(QWidget):    def __init__(self,parent=None):        super(Example1,self).__init__(parent)                figure = plt.gcf() #返回当前的figure        self.canvas = figureCanvas(figure)        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)        self.canvas.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas)        class Example2(QWidget):    def __init__(self,parent=None):        super(Example2,self).__init__(parent)                figure1 = plt.figure(1) #返回当前的figure        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example1‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                figure2 = plt.figure(2) #返回当前的figure        x = [7,8,9]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example2‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                self.canvas1 = figureCanvas(figure1)        self.canvas2 = figureCanvas(figure2)        self.canvas1.draw()        self.canvas2.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas1)        layout.addWidget(self.canvas2)        class Example3(QWidget):    def __init__(self,parent=None):        super(Example3,self).__init__(parent)        #         figure1 = plt.figure(1) #返回当前的figure        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example1‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)        #         figure2 = plt.figure(2) #返回当前的figure        x = [7,8,9]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example2‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                self.canvas1 = figureCanvas(plt.gcf())#         self.canvas2 = figureCanvas(figure2)        self.canvas1.draw()#         self.canvas2.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas1)#         layout.addWidget(self.canvas2)            if __name__ == ‘__main__‘:    app = QApplication(sys.argv)    ui = Example3()    ui.show()    app.exec_()

#_*_coding:utf-8_*_‘‘‘Created on 2014年12月10日@author: Administrator‘‘‘from PyQt4.QtCore import *from PyQt4.QtGui import *from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvasimport matplotlib.pyplot as pltimport sysclass Example1(QWidget):    def __init__(self,parent=None):        super(Example1,self).__init__(parent)                figure = plt.gcf() #返回当前的figure        self.canvas = figureCanvas(figure)        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)        self.canvas.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas)        class Example2(QWidget):    def __init__(self,parent=None):        super(Example2,self).__init__(parent)                figure1 = plt.figure(1) #返回当前的figure        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example1‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                figure2 = plt.figure(2) #返回当前的figure        x = [7,8,9]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example2‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                self.canvas1 = figureCanvas(figure1)        self.canvas2 = figureCanvas(figure2)        self.canvas1.draw()        self.canvas2.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas1)        layout.addWidget(self.canvas2)        class Example3(QWidget):    def __init__(self,parent=None):        super(Example3,self).__init__(parent)                figure = plt.figure(figsize=(10,60),facecolor=‘green‘,edgecolor=‘red‘)         #figsize = (8,4)表示figure的大小，屏幕显示 640 * 320 ， 输出显示 800*400，这个要注意。        #显示色和外框线条颜色设置。        self.canvas = figureCanvas(figure)                plt.subplot(211) # 子区，2行，2列        x = [1,2,3]        y = [4,5,6]        plt.plot(x,y)        plt.title(‘Example‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                plt.subplot(223) # 子区，2行，2列        x = [1,2,3]        y = [4,5,6]        plt.bar(x,y)        plt.title(‘Example‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                plt.subplot(224) # 子区，2行，2列        x = [1,2,3]        y = [4,5,6]        plt.scatter(x,y)        plt.title(‘Example‘)        plt.xlabel(‘x‘)        plt.ylabel(‘y‘)                self.canvas.draw()        layout = QHBoxLayout(self)        layout.addWidget(self.canvas)            if __name__ == ‘__main__‘:    app = QApplication(sys.argv)    ui = Example3()    ui.show()    app.exec_()

#_*_coding:utf-8_*_‘‘‘Created on 2014年12月10日@author: Administrator‘‘‘from PyQt4.QtCore import *from PyQt4.QtGui import *from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvasimport matplotlib.pyplot as pltimport numpy as npimport sysclass Example1(QWidget):    def __init__(self,parent=None):        super(Example1,self).__init__(parent)        figure = plt.figure(figsize=(10,6),dpi=100,facecolor=‘white‘)        canvas = figureCanvas(figure)        x = np.linspace(-np.pi,np.pi,256,endpoint=True)        c = np.cos(x)        s = np.sin(x)        plt.plot(x,c,color=‘blue‘,linewidth=1.0,linestyle=‘-‘,label=‘$cos(x)$‘)#设置颜色，线条的格式和粗细        plt.plot(x,s,color=‘green‘,linewidth=1.0,linestyle=‘-‘,label=‘$sin(x)$‘)                ax = plt.gca()        ax.spines[‘right‘].set_color(‘none‘)        ax.spines[‘top‘].set_color(‘none‘)        ax.xaxis.set_ticks_position(‘bottom‘)        ax.spines[‘bottom‘].set_position((‘data‘,0))        ax.yaxis.set_ticks_position(‘left‘)        ax.spines[‘left‘].set_position((‘data‘,0))                plt.xlim(x.min()*1.1,x.max()*1.1)#X轴的范围        plt.xticks([-np.pi,-np.pi/2,0,np.pi/2,np.pi],                   [r‘$-\pi$‘,r‘$-\pi/2$‘,r‘$0$‘,r‘$\pi/2$‘,r‘$\pi$‘])#X轴的刻度值        plt.ylim(s.min()*1.1,s.max()*1.1)#Y轴的范围        plt.yticks([-1,0,1],[r‘$-1$‘,r‘$0$‘,r‘$+1$‘]) #设置Y轴的刻度值,第二个参数对其进行格式化                #添加注释和箭头以及虚线        t = np.pi *2 / 3        plt.plot([t,t],[0,np.sin(t)],color=‘red‘,linewidth=2.5,linestyle=‘--‘)        plt.scatter([t],[np.sin(t)],50,color=‘red‘) #50代表散点的大小，应该是像素值                plt.plot([t,t],[0,np.cos(t)],color=‘green‘,linewidth=2.5,linestyle=‘--‘)        plt.scatter([t],[np.cos(t)],50,color=‘green‘)                        plt.annotate(r‘$sin(\frac{2\pi}{3})=(\frac{\sqrt{3}}{2})$‘,                     xy=(t,np.sin(t)),xycoords=‘data‘,                     xytext=(10,30),textcoords=‘offset points‘,fontsize=16,                     arrowprops = dict(arrowstyle=‘->‘,connectionstyle=‘arc3,rad=.1‘))        plt.annotate(r‘$cos(\frac{2\pi}{3})=(\frac{\sqrt{3}}{2})$‘,                     xy=(t,np.cos(t)),xycoords=‘data‘,                     xytext=(-120,-30),textcoords = ‘offset points‘,fontsize=16,                     arrowprops = dict(arrowstyle=‘->‘,connectionstyle=‘arc3,rad=.1‘)) #后面的参数应该是角度，类似于偏离度，1的时候接近垂直        plt.legend(loc=‘upper left‘)                for i in ax.get_xticklabels() + ax.get_yticklabels():            i.set_fontsize(15)            i.set_bbox(dict(facecolor=‘white‘,edgecolor=‘none‘,alpha=0.65))                canvas.draw()        layout = QHBoxLayout(self)        layout.addWidget(canvas)        if __name__ == ‘__main__‘:    app = QApplication(sys.argv)    ui = Example1()    ui.show()    app.exec_()

#_*_coding:utf-8_*_‘‘‘Created on 2014年12月10日@author: Administrator‘‘‘#_*_coding:utf-8_*_‘‘‘Created on 2014年12月10日@author: Administrator‘‘‘from PyQt4.QtCore import *from PyQt4.QtGui import *from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as figureCanvasimport matplotlib.pyplot as pltimport numpy as npimport sysclass Example1(QWidget):    def __init__(self,parent=None):        super(Example1,self).__init__(parent)        figure = plt.figure(figsize=(10,6),dpi=100,facecolor=‘white‘)        canvas = figureCanvas(figure)                plt.axes([0.1,0.1,0.5,0.5])        plt.xticks([])        plt.yticks([])        plt.text(0.2,0.2,‘hello axes‘,alpha=‘0.65‘,size=16)                plt.text(0.6,0.4,‘hello axes‘,alpha=‘0.65‘,size=16)                canvas.draw()        layout = QHBoxLayout(self)        layout.addWidget(canvas)        if __name__ == ‘__main__‘:    app = QApplication(sys.argv)    ui = Example1()    ui.show()    app.exec_()

>>> fig.set_alpha(0.5*fig.get_alpha())

>>> fig.set(alpha=0.5, zorder=2)

Figure容器

最大的Artist容器是matplotlib.figure.Figure，它包括組成圖表的所有元素。圖表的背景是一個Rectangle對象，用Figure.patch屬性表示。當你通過調用add_subplot或者add_axes方法往圖表中添加軸(子圖時)，這些子圖都將添加到Figure.axes屬性中，同時這兩個方法也返回添加進axes屬性的對象，注意返回值的類型有所不同，實際上AxesSubplot是Axes的子類。

為了支持pylab中的gca()等函數，Figure對像內部保存有當前軸的信息，因此不建議直接對Figure.axes屬性進行列表操作，而應該使用add_subplot, add_axes, delaxes等方法進行添加和刪除操作。但是使用for循環對axes中的每個元素進行操作是沒有問題的，下面的語句打開所有子圖的柵格。>>> for ax in fig.axes: ax.grid(True)

figure提供了一些简单的artist对象，主要还是通过里面的axes对象来实现功能的扩展。因为很多情况下都会默认创建一个subplot和axes对象，当然也可以直接操作，比如：

>>> from matplotlib.lines import Line2D>>> fig = plt.figure()>>> line1 = Line2D([0,1],[0,1], transform=fig.transFigure, figure=fig, color="r")>>> line2 = Line2D([0,1],[1,0], transform=fig.transFigure, figure=fig, color="g")>>> fig.lines.extend([line1, line2])>>> fig.show()

Figure對像有如下屬性包含其它的Artist對像，也就意味着可以通过他们再进行进一步的操作。

• axes : Axes對像列表
• patch : 作為背景的Rectangle對像
• images : FigureImage對像列表，用來顯示圖片
• legends : Legend對像列表
• lines : Line2D對像列表
• patches : patch對像列表
• texts : Text對像列表，用來顯示文字

Axes容器

Axes容器是整個matplotlib庫的核心，它包含了組成圖表的眾多Artist對象，並且有許多方法函數幫助我們創建、修改這些對象。和Figure一樣，它有一個patch屬性作為背景，當它是笛卡爾坐標時，patch屬性是一個Rectangle對象，而當它是極坐標時，patch屬性則是Circle對象。例如下面的語句設置Axes對象的背景顏色為綠色：

>>> fig = plt.figure()>>> ax = fig.add_subplot(111)>>> ax.patch.set_facecolor("green")

下面詳細列出Axes包含各種Artist對象的屬性：

• artists : Artist對像列表
• patch : 作為Axes背景的Patch對象，可以是Rectangle或者Circle
• collections : Collection對像列表
• images : AxesImage對像列表
• legends : Legend對像列表
• lines : Line2D對像列表
• patches : Patch對像列表
• texts : Text對像列表
• xaxis : XAxis對像
• yaxis : YAxis對像

下面列出Axes的創建Artist對象的方法：

Axis容器

Axis容器包括坐標軸上的刻度線、刻度文本、坐標網格以及坐標軸標題等內容。刻度包括主刻度和副刻度，分別通過Axis.get_major_ticks和Axis.get_minor_ticks方法獲得。每個刻度線都是一個XTick或者YTick對象，它包括實際的刻度線和刻度文本。為了方便訪問刻度線和文本，Axis對像提供了get_ticklabels和get_ticklines方法分別直接獲得刻度文本和刻度线：

>>> pl.plot([1,2,3],[4,5,6])[<matplotlib.lines.Line2D object at 0x0AD3B670>]>>> pl.show()>>> axis = pl.gca().xaxis

>>> axis.get_ticklocs() # 獲得刻度的位置列表array([ 1. ,  1.5,  2. ,  2.5,  3. ])

>>> axis.get_ticklabels() # 獲得刻度標籤列表<a list of 5 Text major ticklabel objects>>>> [x.get_text() for x in axis.get_ticklabels()] # 獲得刻度的文本字符串[u‘1.0‘, u‘1.5‘, u‘2.0‘, u‘2.5‘, u‘3.0‘]

>>> axis.get_ticklines() # 獲得主刻度線列表，圖的上下刻度線共10條<a list of 10 Line2D ticklines objects>

>>> axis.get_ticklines(minor=True) # 獲得副刻度線列表，major是主刻度线<a list of 0 Line2D ticklines objects>

>>> axis.get_minor_locator() # 計算副刻度的對象<matplotlib.ticker.NullLocator instance at 0x0A014300>>>> axis.get_major_locator() # 計算主刻度的對象<matplotlib.ticker.AutoLocator instance at 0x09281B20>

# -*- coding: utf-8 -*-import matplotlib.pyplot as plfrom matplotlib.ticker import MultipleLocator, FuncFormatterimport numpy as npx = np.arange(0, 4*np.pi, 0.01)y = np.sin(x)pl.figure(figsize=(8,4))pl.plot(x, y)ax = pl.gca()def pi_formatter(x, pos):    """    比較囉嗦地將數值轉換為以pi/4為單位的刻度文本    """    m = np.round(x / (np.pi/4))    n = 4    if m%2==0: m, n = m/2, n/2    if m%2==0: m, n = m/2, n/2    if m == 0:        return "0"    if m == 1 and n == 1:        return "$\pi$"    if n == 1:        return r"$%d \pi$" % m    if m == 1:        return r"$\frac{\pi}{%d}$" % n    return r"$\frac{%d \pi}{%d}$" % (m,n)# 設置兩個坐標軸的範圍pl.ylim(-1.5,1.5)pl.xlim(0, np.max(x))# 設置圖的底邊距pl.subplots_adjust(bottom = 0.15)pl.grid() #開啟網格# 主刻度為pi/4ax.xaxis.set_major_locator( MultipleLocator(np.pi/4) )# 主刻度文本用pi_formatter函數計算ax.xaxis.set_major_formatter( FuncFormatter( pi_formatter ) )# 副刻度為pi/20ax.xaxis.set_minor_locator( MultipleLocator(np.pi/20) )# 設置刻度文本的大小for tick in ax.xaxis.get_major_ticks():    tick.label1.set_fontsize(16)pl.show()