在NumPy中创建可能包含掩码值的数组类,并设置不同的输出dtype


使用**ma.MaskedArray()**方法创建一个掩码数组。掩码使用“**mask**”参数设置。此处设置为False。数据类型使用“**dtype**”参数设置。掩码数组是标准numpy.ndarray和掩码的组合。掩码要么是nomask,表示关联数组的无任何值无效,要么是布尔数组,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()方法创建一个包含整型元素的数组:

arr = np.array([[77, 51, 92], [56, 31, 69], [73, 88, 51], [62, 45, 67]]) print("Array...", arr) print("Array type...", arr.dtype)

获取数组的维度:

print("Array Dimensions...",arr.ndim)

创建一个掩码数组。掩码使用“mask”参数设置。此处设置为False。数据类型使用“dtype”参数设置:

maskArr = ma.MaskedArray(arr, mask = False, dtype=float) print("Our Masked Array", maskArr) print("Our Masked Array type...", maskArr.dtype)

获取掩码数组的维度:

print("Our Masked Array Dimensions...",maskArr.ndim)

获取掩码数组的形状:

print("Our Masked Array Shape...",maskArr.shape)

获取掩码数组的元素数量:

print("Elements in the Masked Array...",maskArr.size)

示例

Open Compiler
# Python ma.MaskedArray - Create an array class with possibly masked values and set a different dtype of output import numpy as np import numpy.ma as ma # Create an array with int elements using the numpy.array() method arr = np.array([[77, 51, 92], [56, 31, 69], [73, 88, 51], [62, 45, 67]]) print("Array...", arr) print("Array type...", arr.dtype) # Get the dimensions of the Array print("Array Dimensions...",arr.ndim) # Create a masked array # The mask is set using the "mask" parameter. Set to False here # The datatype is set using the "dtype" parameter maskArr = ma.MaskedArray(arr, mask = False, dtype=float) print("Our Masked Array", maskArr) print("Our Masked Array type...", maskArr.dtype) # Get the dimensions of the Masked Array print("Our Masked Array Dimensions...",maskArr.ndim) # Get the shape of the Masked Array print("Our Masked Array Shape...",maskArr.shape) # Get the number of elements of the Masked Array print("Elements in the Masked Array...",maskArr.size)

Explore our latest online courses and learn new skills at your own pace. Enroll and become a certified expert to boost your career.

输出

Array...
[[77 51 92]
[56 31 69]
[73 88 51]
[62 45 67]]

Array type...
int64

Array Dimensions...
2

Our Masked Array
[[77.0 51.0 92.0]
[56.0 31.0 69.0]
[73.0 88.0 51.0]
[62.0 45.0 67.0]]

Our Masked Array type...
float64

Our Masked Array Dimensions...
2

Our Masked Array Shape...
(4, 3)

Elements in the Masked Array...
12

更新于:2022年2月3日

84 次查看

启动您的职业生涯

通过完成课程获得认证

开始
广告