返回 NumPy 中两个带掩码的一维数组的内积
要返回两个带掩码数组的内积,请在 Python NumPy 中使用 **ma.inner()** 方法。对于一维数组,这是向量的普通内积(不进行复共轭);在更高维度上,这是对最后一个轴的求和积。
out 参数表明,如果两个数组都是标量或都是一维数组,则返回标量;否则返回数组。out.shape = (*a.shape[:-1], *b.shape[:-1])。
带掩码数组是标准 numpy.ndarray 和掩码的组合。掩码要么是 nomask(表示关联数组的任何值均有效),要么是布尔值数组,用于确定关联数组的每个元素的值是否有效。
步骤
首先,导入所需的库:
import numpy as np import numpy.ma as ma
使用 numpy.array() 方法创建数组 1,其中包含整数元素:
arr1 = np.array([5, 10, 15, 20, 25])
print("Array1...
", arr1)
print("
Array type...
", arr1.dtype)创建带掩码的数组 1:
arr1 = ma.array(arr1)
掩码数组 1:
arr1[0] = ma.masked arr1[1] = ma.masked
显示带掩码的数组 1:
print("
Masked Array1...
",arr1)
使用 numpy.array() 方法创建另一个数组 2,其中包含整数元素:
arr2 = np.array([7, 14, 21, 28, 35])
print("
Array2...
", arr2)
print("
Array type...
", arr2.dtype)创建一个带掩码的数组 2:
arr2 = ma.array(arr2)
掩码数组 2:
arr2[3] = ma.masked arr2[4] = ma.masked
显示带掩码的数组 2:
print("
Masked Array2...
",arr2)
要返回两个带掩码数组的内积,请在 Python NumPy 中使用 ma.inner() 方法。对于一维数组,这是向量的普通内积(不进行复共轭);在更高维度上,这是对最后一个轴的求和积:
print("
Result of inner product...
",np.ma.inner(arr1, arr2))示例
# Python ma.MaskedArray - Return the inner product of two masked One- Dimensional arrays
import numpy as np
import numpy.ma as ma
# Array 1
# Creating a 1D array with int elements using the numpy.array() method
arr1 = np.array([5, 10, 15, 20, 25])
print("Array1...
", arr1)
print("
Array type...
", arr1.dtype)
# Get the dimensions of the Array
print("
Array Dimensions...
",arr1.ndim)
# Get the shape of the Array
print("
Our Array Shape...
",arr1.shape)
# Get the number of elements of the Array
print("
Elements in the Array...
",arr1.size)
# Create a masked array
arr1 = ma.array(arr1)
# Mask Array1
arr1[0] = ma.masked
arr1[1] = ma.masked
# Display Masked Array 1
print("
Masked Array1...
",arr1)
# Array 2
# Creating another 1D array with int elements using the numpy.array() method
arr2 = np.array([7, 14, 21, 28, 35])
print("
Array2...
", arr2)
print("
Array type...
", arr2.dtype)
# Get the dimensions of the Array
print("
Array Dimensions...
",arr2.ndim)
# Get the shape of the Array
print("
Our Array Shape...
",arr2.shape)
# Get the number of elements of the Array
print("
Elements in the Array...
",arr2.size)
# Create a masked array
arr2 = ma.array(arr2)
# Mask Array2
arr2[3] = ma.masked
arr2[4] = ma.masked
# Display Masked Array 2
print("
Masked Array2...
",arr2)
# To return the inner product of two masked arrays, use the ma.inner() method in Python Numpy
# Ordinary inner product of vectors for 1-D arrays (without complex conjugation), in higher dimensions a sum product over the last axes.
print("
Result of inner product...
",np.ma.inner(arr1, arr2))输出
Array1... [ 5 10 15 20 25] Array type... int64 Array Dimensions... 1 Our Array Shape... (5,) Elements in the Array... 5 Masked Array1... [-- -- 15 20 25] Array2... [ 7 14 21 28 35] Array type... int64 Array Dimensions... 1 Our Array Shape... (5,) Elements in the Array... 5 Masked Array2... [7 14 21 -- --] Result of inner product... 315
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