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I'm trying to shade points in a scatter plot based on a set of values (from 0 to 1) picked from one of the already defined color maps, like Blues or Reds. I tried this:
import matplotlib
import matplotlib.pyplot as plt
from numpy import *
from scipy import *
fig = plt.figure()
mymap = plt.get_cmap("Reds")
x = [8.4808517662594909, 11.749082788323497, 5.9075039082855652, 3.6156231827873615, 12.536817102137768, 11.749082788323497, 5.9075039082855652, 3.6156231827873615, 12.536817102137768]
spaced_colors = linspace(0, 1, 10)
print spaced_colors
plt.scatter(x, x,
color=spaced_colors,
cmap=mymap)
# this does not work either
plt.scatter(x, x,
color=spaced_colors,
cmap=plt.get_cmap("gray"))
But it does not work, using either the Reds or gray color map. How can this be done?
edit: if I want to plot each point separately so it can have a separate legend, how can I do it? I tried:
fig = plt.figure()
mymap = plt.get_cmap("Reds")
data = np.random.random([10, 2])
colors = list(linspace(0.1, 1, 5)) + list(linspace(0.1, 1, 5))
print "colors: ", colors
plt.subplot(1, 2, 1)
plt.scatter(data[:, 0], data[:, 1],
c=colors,
cmap=mymap)
plt.subplot(1, 2, 2)
# attempt to plot first five points in five shades of red,
# with a separate legend for each point
for n in range(5):
plt.scatter([data[n, 0]], [data[n, 1]],
c=[colors[n]],
cmap=mymap,
label="point %d" %(n))
plt.legend()
but it fails. I need to make a call to scatter for each point so that it can have a separate label=, but still want each point to have a different shade of the color map as its color. thanks.