05_array[ ]

list[ ]

array[[ ],[ ] ]

Array

List [1,2,3]

List *2 會變成 [1,2,3,1,2,3]

但將list轉為array，便可運算

arr=array(list)

arr=([1,2,3])

arr *2 = [2,4,6]

矩陣相加的和 

x = [[12,7,3],

        [4,5,6],

        [7,8,9]]

y = [[5,8,1],

        [6,7,3],

        [4,5,9]]

z= []

for i in range(3):

    z.append([])

for i in range(3):

    for j in range(3):

        z[i].append(x[i][j]*y[i][j])

s=np.sum(z)

print(z)

print (s)

矩陣相乘

X = [[12,7,3],

    [4 ,5,6],

    [7 ,8,9]]

Y = [[5,8,1],

    [6,7,3],

    [4,5,9]]

result = [[0,0,0],

         [0,0,0],

         [0,0,0]]

# 輸出行

for i in range(len(X)):

   # 輸出列

   for j in range(len(X[0])):

       result[i][j] = X[i][j] * Y[i][j]