使用mat创建矩阵

a = np.mat([[5, 6], [7, 8]])
b = np.mat([[1, 2], [3, 4]])
print(a)
print(b)
print(type(a))
print(type(b))

矩阵的加减乘除运算

data1 = np.mat([[1, 2], [3, 4], [5, 6]])
data2 = np.mat([1, 2])
data3 = np.mat([[5, 6], [7, 8]])
print(data1 + data2)
print(data1 - data2)
print(data1 / data2)
print(data1 * data3)

数组点乘运算

n1 = np.array([1, 2, 3])
n2 = np.array([[1, 2, 3], [1, 2, 3], [1, 2, 3]])
print(np.multiply(n1, n2))

矩阵求转置

n1 = np.mat([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
print('矩阵转置结果为：\n', n1.T)

矩阵求逆

n1 = np.mat([[1, 3, 3], [4, 5, 6], [7, 15, 9]])
print('矩阵的逆矩阵结果为：\n', n1.I)

使用Numpy内置函数进行数组加减乘除

n1 = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
n2 = np.array([10, 10, 10])
print('两个数组相加：')
print(np.add(n1, n2))
print('两个数组相减：')
print(np.subtract(n1, n2))
print('两个数组相乘：')
print(np.multiply(n1, n2))
print('两个数组相除：')
print(np.divide(n1, n2))

幂运算

n1 = np.array([10, 100, 1000])
print(np.power(n1, 3))

数组元素行列求和

n = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
print('对数组元素求和：')
print(n.sum())
print('对数组元素按列求和：')
print(n.sum(axis=0))
print('对数组元素按行求和：')
print(n.sum(axis=1))

数组元素求平均值

n = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
print('对数组元素求平均值：')
print(n.mean())
print('对数组元素按列求平均值：')
print(n.mean(axis=0))
print('对数组元素按行求平均值：')
print(n.mean(axis=1))

求最大最小值

n = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
print('数组元素最大值：')
print(n.max())
print('数组中每一列的最大值：')
print(n.max(axis=0))
print('数组中每一行的最大值：')
print(n.max(axis=1))
print('数组元素最小值：')
print(n.min())
print('数组中每一列的最小值：')
print(n.min(axis=0))
print('数组中每一行的最小值：')
print(n.min(axis=1))

求数组中位数

n = np.array([34.5, 36, 37.8, 39, 39.8, 33.6])
# 数组排序后，查找中位数
sort_n = np.sort(n)
print('数组排序：')
print(sort_n)
print('数组中位数为：')
print(np.median(sort_n))

求数组方差标准差

n = np.array([34.5, 36, 37.8, 39, 39.8, 33.6])
print('数组方差：')
print(np.var(n))
print('数组标准差：')
print(np.std(n))

数组排序

n = np.array([[4, 7, 3], [2, 8, 5], [9, 1, 6]])
print('数组排序：')
print(np.sort(n))
print('按列排序：')
print(np.sort(n, axis=0))
print('按行排序：')
print(np.sort(n, axis=1))