CS231n(一):基礎知識
阿新 • • 發佈:2017-05-21
深度學習 highlight 自己 元組 .py [0 upper bsp python
給自己新挖個坑:開始刷cs231n深度學習。
看了一下導言的pdf,差缺補漏。
s = "hello" print s.capitalize() # 首字母大寫; prints "Hello" print s.upper() # 全部大寫; prints "HELLO" print s.rjust(7) #空格; prints " hello" print s.center(7) # 居中; prints " hello " print s.replace(‘l‘, ‘(ell)‘) # 替換; # prints"he(ell)(ell)o" print ‘ world ‘.strip() # Strip leading and trailing whitespace; prints "world"
切片和索引
nums = range(5) # 生成[0,1,2,3,4] print nums print nums[:] # 全部輸出; prints "[0, 1, 2, 3, 4]" print nums[:-1] # 倒數第一個直接用-1; prints "[0, 1, 2, 3]"
元組
d = {(x, x + 1): x for x in range(10)} #創建元組型字典 t = (5, 6) # 創建元組 print type(t) # Prints "<type ‘tuple‘>" print d[t] # Prints "5" print d[(1, 2)] # Prints "1"
創建空array
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]
矩陣轉置
a = np.array([[1,2,3],[4,5,6]])
b = a.T#輸出a的轉置
plt
import numpy as np import matplotlib.pyplot as pltx = np.arange(0, 3 * np.pi, 0.1) y = np.sin(x) plt.plot(x, y) plt.show()
subplot
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()
以上
:)
CS231n(一):基礎知識