在 Numpy 中查找掩码数组沿给定轴的连续未掩码数据


要查找掩码数组沿给定轴的连续未掩码数据,请在 Python Numpy 中使用 **numpy.ma.notmasked_contiguous**。该方法返回数组中未掩码索引的切片(起始和结束索引)列表。如果输入是二维的并且指定了轴,则结果是一个列表的列表。

轴是执行操作的轴。如果为 None(默认值),则应用于数组的扁平化版本,这与 flatnotmasked_contiguous 相同。

步骤

首先,导入所需的库 -

import numpy as np
import numpy.ma as ma

使用 numpy.array() 方法创建包含整数元素的数组 -

arr = np.array([[65, 68, 81], [93, 33, 39], [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)

创建一个掩码数组并将其中的某些元素标记为无效 -

maskArr = ma.masked_array(arr, mask =[[1, 1, 0], [ 1, 0, 0], [0, 1, 0], [0, 1, 0]])
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)

返回一个布尔值,指示数据是否连续 -

print("
Check whether the data is contiguous?
",maskArr.iscontiguous())

要查找掩码数组沿给定轴的连续未掩码数据,请使用 numpy.ma.notmasked_contiguous

print("
Result...
",np.ma.notmasked_contiguous(maskArr, axis = 0))

示例

import numpy as np
import numpy.ma as ma

# Create an array with int elements using the numpy.array() method
arr = np.array([[65, 68, 81], [93, 33, 39], [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 and mask some of them as invalid maskArr = ma.masked_array(arr, mask =[[1, 1, 0], [ 1, 0, 0], [0, 1, 0], [0, 1, 0]]) 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) # Return a boolean indicating whether the data is contiguous print("
Check whether the data is contiguous?
",maskArr.iscontiguous()) # To find contiguous unmasked data in a masked array along the given axis, use the numpy.ma.notmasked_contiguous in Python Numpy print("
Result...
",np.ma.notmasked_contiguous(maskArr, axis = 0))

输出

Array...
[[65 68 81]
[93 33 39]
[73 88 51]
[62 45 67]]

Array type...
int64

Array Dimensions...
2

Our Masked Array
[[-- -- 81]
[-- 33 39]
[73 -- 51]
[62 -- 67]]

Our Masked Array type...
int64

Our Masked Array Dimensions...
2

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

Elements in the Masked Array...
12

Check whether the data is contiguous?
True
Result...
[[slice(2, 4, None)], [slice(1, 2, None)], [slice(0, 4, None)]]

更新于: 2022年2月4日

124 次查看

开启你的 职业生涯

通过完成课程获得认证

开始
广告