返回 NumPy 中一維陣列未掩蓋塊對應的切片列表
要返回與一維陣列未掩蓋塊對應的切片列表,請使用 Python NumPy 中的 **ma.clump_unmasked()**。“塊”定義為陣列的連續區域。返回切片列表,每個切片對應陣列中一個連續的未掩蓋元素區域。
掩碼陣列是標準 numpy.ndarray 和掩碼的組合。掩碼要麼是 nomask(表示關聯陣列中沒有無效值),要麼是布林陣列,它確定關聯陣列的每個元素的值是否有效。
步驟
首先,匯入所需的庫:
import numpy as np import numpy.ma as ma
使用 numpy.array() 方法建立一個包含整型元素的陣列:
arr = np.array([65, 68, 81, 93, 33, 39, 62, 45, 67])
print("Array...
", arr)
print("
Array type...
", arr.dtype)獲取陣列的維度:
print("
Array Dimensions...
",arr.ndim)
建立一個掩碼陣列並將其中一些元素標記為無效:
maskArr = ma.masked_array(arr, mask =[1, 1, 0, 1, 0, 0, 0, 1, 0])
print("
Our Masked Array
", maskArr)
print("
Our Masked Array type...
", maskArr.dtype)獲取掩碼陣列的維度:
print("
Our Masked Array Dimensions...
",maskArr.ndim)
獲取掩碼陣列的形狀:
print("
Our Masked Array Shape...
",maskArr.shape)獲取掩碼陣列的元素個數:
print("
Elements in the Masked Array...
",maskArr.size)
返回一個布林值,指示資料是否連續:
print("
Check whether the data is contiguous?
",maskArr.iscontiguous())要返回與一維陣列未掩蓋塊對應的切片列表,請使用 ma.clump_unmasked()。“塊”定義為陣列的連續區域:
print("
Result...
",np.ma.clump_unmasked(maskArr))
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, 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])
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 return a list of slices corresponding to the unmasked clumps of a 1-D array, use the ma.clump_unmasked() in Python Numpy
# A "clump" is defined as a contiguous region of the array.
print("
Result...
",np.ma.clump_unmasked(maskArr))輸出
Array... [65 68 81 93 33 39 62 45 67] Array type... int64 Array Dimensions... 1 Our Masked Array [-- -- 81 -- 33 39 62 -- 67] Our Masked Array type... int64 Our Masked Array Dimensions... 1 Our Masked Array Shape... (9,) Elements in the Masked Array... 9 Check whether the data is contiguous? True Result... [slice(2, 3, None), slice(4, 7, None), slice(8, 9, None)]
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