Note
Go to the endto download the full example code.
Span Selector#
TheSpanSelector is a mouse widget that enables selecting a range on anaxis.
Here, an x-range can be selected on the upper axis; a detailed view of theselected range is then plotted on the lower axis.
Note
If the SpanSelector object is garbage collected you will lose theinteractivity. You must keep a hard reference to it to prevent this.
importmatplotlib.pyplotaspltimportnumpyasnpfrommatplotlib.widgetsimportSpanSelector# Fixing random state for reproducibilitynp.random.seed(19680801)fig,(ax1,ax2)=plt.subplots(2,figsize=(8,6))x=np.arange(0.0,5.0,0.01)y=np.sin(2*np.pi*x)+0.5*np.random.randn(len(x))ax1.plot(x,y)ax1.set_ylim(-2,2)ax1.set_title('Press left mouse button and drag ''to select a region in the top graph')line2,=ax2.plot([],[])defonselect(xmin,xmax):indmin,indmax=np.searchsorted(x,(xmin,xmax))indmax=min(len(x)-1,indmax)region_x=x[indmin:indmax]region_y=y[indmin:indmax]iflen(region_x)>=2:line2.set_data(region_x,region_y)ax2.set_xlim(region_x[0],region_x[-1])ax2.set_ylim(region_y.min(),region_y.max())fig.canvas.draw_idle()span=SpanSelector(ax1,onselect,"horizontal",useblit=True,props=dict(alpha=0.5,facecolor="tab:blue"),interactive=True,drag_from_anywhere=True)# Set useblit=True on most backends for enhanced performance.plt.show()
References
The use of the following functions, methods, classes and modules is shownin this example: