Flattening refers to either reducing a multi-dimensional array to a single dimension or to reducing a class and class methods to handle based function calls.
Questions tagged [flatten]
1554 questions
5192
votes
33 answers
How do I make a flat list out of a list of lists?
I have a list of lists like
[
[1, 2, 3],
[4, 5, 6],
[7],
[8, 9]
]
How can I flatten it to get [1, 2, 3, 4, 5, 6, 7, 8, 9]?
If your list of lists comes from a nested list comprehension, the problem can be solved more simply/directly…
Emma
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votes
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Merge/flatten an array of arrays
I have a JavaScript array like:
[["$6"], ["$12"], ["$25"], ["$25"], ["$18"], ["$22"], ["$10"]]
How would I go about merging the separate inner arrays into one like:
["$6", "$12", "$25", ...]
Andy
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550
votes
51 answers
Flatten an irregular (arbitrarily nested) list of lists
Yes, I know this subject has been covered before:
Python idiom to chain (flatten) an infinite iterable of finite iterables?
Flattening a shallow list in Python
Comprehension for flattening a sequence of sequences?
How do I make a flat list out of a…
telliott99
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votes
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What is the difference between flatten and ravel functions in numpy?
import numpy as np
y = np.array(((1,2,3),(4,5,6),(7,8,9)))
OUTPUT:
print(y.flatten())
[1 2 3 4 5 6 7 8 9]
print(y.ravel())
[1 2 3 4 5 6 7 8 9]
Both function return the same list.
Then what is the need of two…
cryptomanic
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votes
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How to Flatten a Multidimensional Array?
Is it possible, in PHP, to flatten a (bi/multi)dimensional array without using recursion or references?
I'm only interested in the values so the keys can be ignored, I'm thinking in the lines of array_map() and array_values().
Alix Axel
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votes
8 answers
Turn Pandas Multi-Index into column
I have a dataframe with 2 index levels:
value
Trial measurement
1 0 13
1 3
2 4
2 0 NaN
1 12
…
TheChymera
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votes
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How to flatten only some dimensions of a numpy array
Is there a quick way to "sub-flatten" or flatten only some of the first dimensions in a numpy array?
For example, given a numpy array of dimensions (50,100,25), the resultant dimensions would be (5000,25)
IssamLaradji
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71
votes
4 answers
How to flatten a pandas dataframe with some columns as json?
I have a dataframe df that loads data from a database. Most of the columns are json strings while some are even list of jsons. For example:
id name columnA columnB
1 John {"dist": "600", "time":…
sfactor
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votes
4 answers
Is it possible to flatten MongoDB result query?
I have a deeply nested collection in my MongoDB collection.
When I run the following query:
db.countries.findOne({},{'data.country.neighbor.name':1,'_id':0})
I end up with this nested result here:
{"data" : {
"country" : [
{
"neighbor"…
Marsellus Wallace
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62
votes
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Flatten a javascript object to pass as querystring
I have a javascript object that I need to flatten into a string so that I can pass as querystring, how would I do that? i.e:
{ cost: 12345, insertBy: 'testUser' } would become cost=12345&insertBy=testUser
I can't use jQuery AJAX call for this call,…
Saxman
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56
votes
10 answers
How to flatten array in jQuery?
How to simply flatten array in jQuery? I have:
[1, 2, [3, 4], [5, 6], 7]
And I want:
[1, 2, 3, 4, 5, 6, 7]
extern.fx
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votes
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JavaScript flattening an array of arrays of objects
I have an array which contains several arrays, each containing several objects, similar to this.
[[object1, object2],[object1],[object1,object2,object3]]
Here is a screenhot of the object logged to the console.
What would be the best approach to…
byrdr
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54
votes
7 answers
How to flatten a list to a list without coercion?
I am trying to achieve the functionality similar to unlist, with the exception that types are not coerced to a vector, but the list with preserved types is returned instead. For instance:
flatten(list(NA, list("TRUE", list(FALSE), 0L))
should…
eold
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46
votes
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Flatten array with objects into 1 object
Given input:
[{ a: 1 }, { b: 2 }, { c: 3 }]
How to return:
{ a: 1, b: 2, c: 3 }
For arrays it's not a problem with lodash but here we have array of objects.
Szymon Toda
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12 answers
How to "flatten" or "index" 3D-array in 1D array?
I am trying to flatten 3D array into 1D array for "chunk" system in my game. It's a 3D-block game and basically I want the chunk system to be almost identical to Minecraft's system (however, this isn't Minecraft clone by any measure). In my previous…
user925777