05

'''
匯入套件
'''
import numpy as np

'''
建立ndarray
'''
# 一維陣列/矩陣創建
data = [1,2,4,8]  #list
np_data = np.array(data) #Numpy array

'''
基本運算
'''
# Basic Operations
print ("Numpy Array:" , np_data)
print ("加:", np_data + np_data)
print ("減:" , np_data - np_data)
print ("乘:" , np_data * np_data)
print ("除:" , np_data / np_data)
print ("*0.5" , np_data * 0.5)

'''
取值
'''
print ("Index 2:", np_data[2])
print ("Index 0-2:" , np_data[0:2])

'''
多維數列（矩陣）創建
'''
data = [[1,2,4,8],[1,3,5,7],[3,6,9,12]]
np_data = np.array(data) #Numpy ndarray
print ("Numpy ndArray:\n", np_data)
print ("Dimensions:" , np_data.shape)  #維度：n*m

'''
基本運算
'''
# Basic Operations
print ("加:\n", np_data + np_data)
print ("減:\n" , np_data - np_data)
print ("乘:\n" , np_data * np_data) #非矩陣相乘
print ("除:\n" , np_data / np_data)
print ("*0.5\n" , np_data * 0.5)

'''
取值
'''
#Indexing
print ("Index 2:\n" , np_data[2])
print ("Index (2,0):\n" , np_data[2][0])
print ("Index 0-2:\n" , np_data[0:2])

'''
統計運算
'''
print ("absolute value:\n" , np.absolute(np_data * -0.5))#絕對值
print ("square root:\n" , np.sqrt(np_data)) #平方根
print ("log(base e):\n" , np.log(np_data)) #log(base e)
print ("Mean:" , np_data.mean()) #np.mean(np_data) also works
print ("Std:" , np_data.std()) #np.std(np_data) also works
print ("Sum:" , np_data.sum()) #np.sum(np_data) also works
print ("Max:" , np_data.max()) #np.(np_data) also works

'''
矩陣運算
'''
data1 = np.array([[1,2,3],[2,4,6]]) #2*3
data2 = np.array([[0,0,0],[1,1,1]]) #2*3
print ("元素相乘:\n" , data1 * data2)
print ("轉置矩陣(Transpose)\n" , data2.transpose())
print ("矩陣相乘:\n" , np.dot(data1, data2.transpose()))