Flatten usage in Python

Flatten usage in Pythonoriginal April 16, 2014 10:20:02

• Label:
• Python/
• Flatten

• 22667

One, used in the array

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1. >>> a = [[1,3],[2,4],[3,5]]
2. >>> A = Array (a)
3. >>> A.flatten ()
4. Array ([1, 3, 2, 4, 3, 5])

Second, use in the list

If you use the Flatten function directly, you will get an error

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1. >>> a = [[1,3],[2,4],[3,5]]
2. >>> A.flatten ()
4. Traceback (most recent):
5. File "<pyshell#10>", line 1, in <module>
6. A.flatten ()
7. Attributeerror: ' List ' object has no attribute ' flatten '

The right usage

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1. >>> a = [[1,3],[2,4],[3,5],["abc","Def"]]
2. >>> a1 = [Y for X in a for y in x]
3. >>> A1
4. [1, 3, 2, 4, 3, 5, ' abc ', ' def ']

or (not understood)

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2. >>> a = [[1,3],[2,4],[3,5],["abc","Def"]]
4. >>> flatten = lambda x: [Y for L in X for y in flatten (l)] if Type (x) is list els e [x]
6. >>> Flatten (a)
8. [1, 3, 2, 4, 3, 5, ' abc ', ' def ']

Third, used in the matrix [Python]View PlainCopy

2. >>> a = [[1,3],[2,4],[3,5]]
4. >>> A = Mat (a)
6. >>> y = A.flatten ()
8. >>> y
10. Matrix ([[[1, 3, 2, 4, 3, 5]])
12. >>> y = A.flatten (). A
14. >>> y
16. Array ([[1, 3, 2, 4, 3, 5]])
18. >>> shape (y)
20. (1, 6)
22. >>> shape (y[0])
24. (6,)
26. >>> y = A.flatten (). a[0]
28. >>> y
30. Array ([1, 3, 2, 4, 3, 5])

Flatten usage in Python