Scatter plot with a slider in python

问题

Hey I am trying to create a scatter plot with a slider that updates the plot as I slide across. This is my code so far. It draws a scatter plot and a slider but as I move it around, nothing happens. I suspect that the problem is with the .set_ydatabit but I can't seem to find how to do it otherwise on the Internet.

import numpy as np 
from matplotlib.widgets import Slider
from pylab import plot, show, figure, scatter, axes, draw

fig = figure()
ax = fig.add_subplot(111)

x, y = np.random.rand(2,100)
scat = scatter(x,y)

axcolor = 'lightgoldenrodyellow'
axamp = axes([0.2, 0.01, 0.65, 0.03], axisbg=axcolor)

scorr = Slider(axamp, 'corr', -2,2, valinit=1)

def update(val):
    corr = scorr.val

    for i in range(len(x)):
        x[i]=x[i]+corr*np.random.randn()

    for i in range(len(y)):
        y[i]=y[i]+corr*np.random.randn()

    scat.set_xdata(x)
    scat.set_ydata(y)
    draw()

scorr.on_changed(update)

show(scat)

This is just a test script in fairness. I have to do the same thing with a much more complicated script but realized it would be easier to try it out on a simpler problem. I really just care about scat.set_ydata and what to put there instead so that it works.

Thanks in advance.

回答1:

You need to use set_offsets and set_array in stead:

# make sure you get the right dimensions and direction of arrays here
xx = np.vstack ((x, y))
scat.set_offsets (xx.T)

# set colors
scat.set_array (y)

Probably duplicate of: How to animate a scatter plot?

来源：https://stackoverflow.com/questions/38368990/scatter-plot-with-a-slider-in-python