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法律研究将掩码数组的数据作为 ndarray 返回
要将掩码数组的数据作为 ndarray 返回，请在 Python Numpy 中使用 **ma.getdata()** 方法。如果 a 是 MaskedArray，则返回其数据（如果有）作为 ndarray；否则，如果 a 不是 MaskedArray，则将其作为 ndarray 或子类返回。
subok 参数建议是否强制输出为纯 ndarray (False) 或者在合适的情况下返回 ndarray 的子类 (True，默认值)。
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.arange() 方法创建一个包含整数元素的 4x4 数组 -
arr = np.arange(16).reshape((4,4))
print("Array...
", arr)
print("
Array type...
", arr.dtype)获取数组的维度 -
print("
Array Dimensions...
",arr.ndim)
获取数组的形状 -
print("
Our Masked Array Shape...
",arr.shape)获取数组的元素个数 -
print("
Elements in the Masked Array...
",arr.size)
创建一个掩码数组 -
arr = ma.array(arr) arr[0, 1] = ma.masked arr[1, 1] = ma.masked arr[2, 1] = ma.masked arr[2, 2] = ma.masked arr[3, 0] = ma.masked arr[3, 2] = ma.masked arr[3, 3] = ma.masked
沿特定轴计算掩码元素的数量 -
print("
The number of masked elements...
",ma.count_masked(arr, axis = 1))
返回掩码数组的掩码 -
print("
The mask of a masked array)...
",ma.getmask(arr))要将掩码数组的数据作为 ndarray 返回，请在 Python Numpy 中使用 ma.getdata() 方法 -
print("
Result (data of a masked array as an ndarray)...
",ma.getdata(arr))
示例
import numpy as np
import numpy.ma as ma
# Creating a 4x4 array with int elements using the numpy.arange() method
arr = np.arange(16).reshape((4,4))
print("Array...
", arr)
print("
Array type...
", arr.dtype)
# Get the dimensions of the Array
print("
Array Dimensions...
",arr.ndim)
print("
Our Array type...
", arr.dtype)
# Get the shape of the Array
print("
Our Masked Array Shape...
",arr.shape)
# Get the number of elements of the Array
print("
Elements in the Masked Array...
",arr.size)
# Create a masked array
arr = ma.array(arr)
arr[0, 1] = ma.masked
arr[1, 1] = ma.masked
arr[2, 1] = ma.masked
arr[2, 2] = ma.masked
arr[3, 0] = ma.masked
arr[3, 2] = ma.masked
arr[3, 3] = ma.masked
# Count the number of masked elements along specific axis
print("
The number of masked elements...
",ma.count_masked(arr, axis = 1))
# Return the mask of a masked array
print("
The mask of a masked array)...
",ma.getmask(arr))
# To return the data of a masked array as an ndarray, use the ma.getdata() method in Python Numpy
print("
Result (data of a masked array as an ndarray)...
",ma.getdata(arr))输出
Array... [[ 0 1 2 3] [ 4 5 6 7] [ 8 9 10 11] [12 13 14 15]] Array type... int64 Array Dimensions... 2 Our Array type... int64 Our Masked Array Shape... (4, 4) Elements in the Masked Array... 16 The number of masked elements... [1 1 2 3] The mask of a masked array)... [[False True False False] [False True False False] [False True True False] [ True False True True]] Result (data of a masked array as an ndarray)... [[ 0 1 2 3] [ 4 5 6 7] [ 8 9 10 11] [12 13 14 15]]
更新于: 2022-02-18
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