Python:matplotlib - 黑白散点图

Question

我觉得我在这里遗漏了一些非常明显的东西，但我无法在 pylab 中获得散点图以黑白打印。任何和所有帮助将不胜感激。这是我的代码:

from pylab import *
from random import random
ioff()

r = range(10)
x = [3 + i + random() for i in r]
y = [50*i + random() for i in r]
x2 = [5 + i + random() for i in r]
y2 = [5*i + random() for i in r]

scatter(x,y, marker = 'o', hold = True, label = 'collected underwear',cmap=cm.Greys)
scatter(x2,y2, marker = 's', hold = True, label = 'Profit!',cmap=cm.Greys)
legend(loc='upper left')

show()

谢谢，

亚当

Answer 1

如果你只是想任意指定颜色，做

color="k"

为黑色，做

color="0.x"

对于灰度，x 可以是任何数字，只要 0.x 介于 0 和 1 之间。

但是如果你想让标记的颜色由另一个数组 z 决定，做

scatter(x,y,c=z, cmap=cm.Greys)

所以对于

from pylab import *
from random import random
r = range(10)
x = [3 + i + random() for i in r]
y = [50*i + random() for i in r]
x2 = [5 + i + random() for i in r]
y2 = [5*i + random() for i in r]
z2 = [i + random() for i in r]
scatter(x,y,   c="0.1", marker = 'o', hold = True, label = 'collected underwear')
scatter(x2,y2, c=z2,marker = 's',  hold = True, label = 'Profit!',cmap=cm.Greys)
legend(loc='upper left')
show()

你会拥有