Re: [Matplotlib-users] redefining scatter positions

[John H. <jdh...@ac...>]

>>>>> "Jeff" == Jeff Peery <jef...@ya...> writes:

    Jeff> Hello, I am having trouble with scatter plots. I created a
    Jeff> scatter plot of just one point: s1 = scatter([1,],[1,])
  
    Jeff>   now I want to move this point after its creation and I'm
    Jeff> not sure how to do this. I'm been looking around in teh
    Jeff> documentation without any success. Is there something that
    Jeff> might be close to the following:

It is possible but not advisable.  scatter will be slower than plot
for this purpose, and since you have only one point there is not
reason to use a PolygonCollection, which is what scatter uses under
the hood.  You can just

  line, = ax.plot([1], [1])

and then call
  
    Jeff>   
  line.set_xydata([2,],[2,])

But if I were just doing one point, I would create my own
matplotlib.patches.Polygon and use ax.add_patch to add it to the axes
and then manipulate the polygon properties directly.

  mpl/examples> grep Polygon *
  integral_demo.py:from matplotlib.patches import Polygon
  integral_demo.py:poly = Polygon(verts, facecolor=0.8, edgecolor='k')
  poly_editor.py:from matplotlib.patches import Polygon
  poly_editor.py:class PolygonInteractor:
  poly_editor.py:p = PolygonInteractor( circ)
  
  mpl/examples> grep Circle *
  picker_demo.py:    p = Circle(center, radius=.1)
  poly_editor.py:circ = Circle((.5,.5),.5)


JDH