在Python中生成给定次数的Vandermonde矩阵

要生成给定次数的Vandermonde矩阵，在Python的Numpy中使用polynomial.polyvander()方法。该方法返回Vandermonde矩阵。返回矩阵的形状是x.shape + (deg + 1,)，其中最后一个索引是x的幂次。dtype将与转换后的x相同。参数a是点的数组。dtype将根据元素是否为复数而转换为float64或complex128。如果x是标量，则将其转换为1-D数组。参数deg是结果矩阵的次数。

步骤

首先，导入所需的库−

import numpy as np
from numpy.polynomial.polynomial import polyvander

创建一个数组 –

x = np.array([0, 1, -1, 2])

显示数组 –

print("Our Array...\n",x)

检查尺寸−

print("\nDimensions of our Array...\n",x.ndim)

获取数据类型 –

print("\nDatatype of our Array object...\n",x.dtype)

获取形状

print("\nShape of our Array object...\n",x.shape)

要生成给定次数的范德蒙矩阵，请使用Python Numpy中的polynomial.polyvander()函数。

print("\nResult...\n",polyvander(x, 2))

样例

import numpy as np
from numpy.polynomial.polynomial import polyvander

# Create an array
x = np.array([0, 1, -1, 2])

# Display the array
print("Our Array...\n",x)

# Check the Dimensions
print("\nDimensions of our Array...\n",x.ndim)

# Get the Datatype
print("\nDatatype of our Array object...\n",x.dtype)

# Get the Shape
print("\nShape of our Array object...\n",x.shape)

# To generate a Vandermonde matrix of given degree, use the polynomial.polyvander() in Python Numpy
print("\nResult...\n",polyvander(x, 2))

输出

Our Array...
[ 0 1 -1 2]

Dimensions of our Array...
1

Datatype of our Array object...
int64

Shape of our Array object...
(4,)

Result...
[[ 1. 0. 0.]
[ 1. 1. 1.]
[ 1. -1. 1.]
[ 1. 2. 4.]]