use custom colormaps with scatter and colorbra

colormap_scatter.py

#!/usr/bin/env python
#coding=utf-8

from matplotlib import cm
from matplotlib import colors
import numpy as np
import matplotlib.pyplot as plt

cm = colors.LinearSegmentedColormap.from_list(
        "my_cmap", #nazwa (bez znaczenia)
        ['0.6', '0.3'], #min i max kolor ('0.3' to znaczy 30% szarosci)
        N=10 # liczba poziomow
        )
xy = np.arange(20)

sc = plt.scatter(xy, xy, c=xy, s=35, cmap=cm)
plt.colorbar(sc)
plt.show()