Get matplotlib color cycle state

Question

Is it possible to query the current state of the matplotlib color cycle? In other words is there a function get_cycle_state that will behave in the following wa

Answer 1

Sure, this will do it.

#rainbow

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0,2*np.pi)
ax= plt.subplot(1,1,1)
ax.plot(np.sin(x))
ax.plot(np.cos(x))

rainbow = ax._get_lines.color_cycle
print rainbow
for i, color in enumerate(rainbow):
    if i<10:
        print color,

Gives:

r c m y k b g r c m

Here is the itertools function that matplotlib uses itertools.cycle

Edit: Thanks for the comment, it seems that it is not possible to copy an iterator. An idea would be to dump a full cycle and keep track of which value you are using, let me get back on that.

Edit2: Allright, this will give you the next color and make a new iterator that behaves as if next was not called. This does not preserve the order of coloring, just the next color value, I leave that to you.

This gives the following output, notice that steepness in the plot corresponds to index, eg first g is the bottomest graph and so on.

#rainbow

import matplotlib.pyplot as plt
import numpy as np
import collections
import itertools

x = np.linspace(0,2*np.pi)
ax= plt.subplot(1,1,1)


def create_rainbow():
    rainbow = [ax._get_lines.color_cycle.next()]
    while True:
        nextval = ax._get_lines.color_cycle.next()
        if nextval not in rainbow:
            rainbow.append(nextval)
        else:
            return rainbow

def next_color(axis_handle=ax):
    rainbow = create_rainbow()
    double_rainbow = collections.deque(rainbow)
    nextval = ax._get_lines.color_cycle.next()
    double_rainbow.rotate(-1)
    return nextval, itertools.cycle(double_rainbow)


for i in range(1,10):
    nextval, ax._get_lines.color_cycle = next_color(ax)
    print "Next color is: ", nextval
    ax.plot(i*(x))


plt.savefig("SO_rotate_color.png")
plt.show()

Console

Next color is:  g
Next color is:  c
Next color is:  y
Next color is:  b
Next color is:  r
Next color is:  m
Next color is:  k
Next color is:  g
Next color is:  c