s = "hello"
print s.capitalize()  # 首字母大写; prints "Hello"
print s.upper()       # 全部大写; prints "HELLO"
print s.rjust(7)      #空格; prints "  hello"
print s.center(7)     # 居中; prints " hello "
print s.replace(‘l‘, ‘(ell)‘)  # 替换;
                               # prints "he(ell)(ell)o"
print ‘  world ‘.strip()  # Strip leading and trailing whitespace; prints "world"

nums = range(5)    # 生成[0,1,2,3,4]
print nums  
print nums[:]      # 全部输出; prints "[0, 1, 2, 3, 4]"
print nums[:-1]    # 倒数第一个直接用-1; prints "[0, 1, 2, 3]"

d = {(x, x + 1): x for x in range(10)}  #创建元组型字典
t = (5, 6)       # 创建元组
print type(t)    # Prints "<type ‘tuple‘>"
print d[t]       # Prints "5"
print d[(1, 2)]  # Prints "1"

v = np.array([1, 0, 1])
y = np.empty_like(v)   # [0,0,0]

v = np.array([1, 0, 1])
vv = np.tile(v, (4, 1))  # [1,0,1]
　　　　　　　　　　　　　　　　　 [1,0,1]
　　　　　　　　　　　　　　　　　　[1,0,1]
　　　　　　　　　　　　　　　　　　[1,0,1]

a = np.array([[1,2,3],[4,5,6]])
b = a.T#输出a的转置

import numpy as np
import matplotlib.pyplot as plt
x = np.arange(0, 3 * np.pi, 0.1)
y = np.sin(x)


plt.plot(x, y)
plt.show()  

import numpy as np
import matplotlib.pyplot as plt

# Compute the x and y coordinates for points on sine and cosine curves
x = np.arange(0, 3 * np.pi, 0.1)
y_sin = np.sin(x)
y_cos = np.cos(x)


plt.subplot(2, 1, 1)


plt.plot(x, y_sin)
plt.title(‘Sine‘)

plt.subplot(2, 1, 2)
plt.plot(x, y_cos)
plt.title(‘Cosine‘)


plt.show()