本文介紹另外幾種常見數(shù)據(jù)圖：Scatter 散點圖、Bar 柱狀圖和 Contours 等高線圖

1. 準(zhǔn)備數(shù)據(jù)

import matplotlib.pyplot as plt
import numpy as np

n = 1024    # data size
X = np.random.normal(0, 1, n)
Y = np.random.normal(0, 1, n)
T = np.arctan2(Y, X)    # for color later on

2. 設(shè)定坐標(biāo)軸

plt.xlim(-1.5, 1.5)
plt.xticks(())  # ignore xticks
plt.ylim(-1.5, 1.5)
plt.yticks(())  # ignore yticks

3. 繪制散點圖

plt.scatter(X, Y, s=75, c=T, alpha=.5)

注：
1.散點圖函數(shù) plt.scatter(X, Y, s, c, alpha)
2.散點圖函數(shù)參數(shù)(X,Y)：表示散點圖上下限點位置
3.散點圖函數(shù)參數(shù)"s"：表示
4.散點圖函數(shù)參數(shù)"c"：表示點的顏色(b--blue弊攘，c--cyan镶柱，g--green，k--black跛璧，m--magenta严里，r--red，w--white追城，y--yellow)
5.散點圖函數(shù)參數(shù)"alpha"：表示點的透明度

4. Bar 柱狀圖

4.1 準(zhǔn)備數(shù)據(jù)

import matplotlib.pyplot as plt
import numpy as np

n = 12
X = np.arange(n)
Y1 = (1 - X / float(n)) * np.random.uniform(0.5, 1.0, n)
Y2 = (1 - X / float(n)) * np.random.uniform(0.5, 1.0, n)

4.2 繪制柱狀圖

plt.bar(X, +Y1, facecolor='#9999ff', edgecolor='white')
plt.bar(X, -Y2, facecolor='#ff9999', edgecolor='white')

注：plt.bar()：(X,Y)表示柱狀圖高度刹碾，facecolor表示柱狀圖顏色，edgecolor表示邊框顏色

4.3 注釋柱狀圖

for x, y in zip(X, Y1):
    # ha: horizontal alignment
    # va: vertical alignment
    plt.text(x + 0.4, y + 0.05, '%.2f' % y, ha='center', va='bottom')

for x, y in zip(X, Y2):
    # ha: horizontal alignment
    # va: vertical alignment
    plt.text(x + 0.4, -y - 0.05, '%.2f' % y, ha='center', va='top')

5. Contours 等高線圖

5.1 準(zhǔn)備數(shù)據(jù)

import matplotlib.pyplot as plt
import numpy as np

def f(x,y):
    # the height function
    return (1 - x / 2 + x**5 + y**3) * np.exp(-x**2 -y**2)

n = 256
x = np.linspace(-3, 3, n)
y = np.linspace(-3, 3, n)
X,Y = np.meshgrid(x, y)

5.2 繪制等高線圖

# use plt.contourf to filling contours
# X, Y and value for (X,Y) point
plt.contourf(X, Y, f(X, Y), 8, alpha=.75, cmap=plt.cm.hot)

注：plt.contourf(X, Y, f(X, Y), 8, alpha=.75, cmap=plt.cm.hot)

5.3 注釋等高線圖

# use plt.contour to add contour lines
C = plt.contour(X, Y, f(X, Y), 8, colors='black', linewidth=.5)
# adding label
plt.clabel(C, inline=True, fontsize=10)

plt.xticks(())
plt.yticks(())
plt.show()