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How to convert a string with comma-delimited items to a list in Python?
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This is not an array, it is a list, Arrays represent basic values and behave very much like lists, except the type of objects stored in them is constrained.
– joaquin
Mar 22 '11 at 6:32
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How to store arrays in MySQL?
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The reason that there are no arrays in SQL, is because most people don't really need it. Relational databases (SQL is exactly that) work using relations, and most of the time, it is best if you assign one row of a table to each "bit of information". For ...
Python - Create a list with initial capacity
...1) * 1000.0))
return res
return wrapper
@print_timing
def prealloc_array (size, init = None, cp = True, cpmethod=copy.deepcopy, cpargs=(), use_num = False):
result = [None] * size
if init is not None:
if cp:
for i in range (size):
result[i] = init
else:
if u...
How do I get the key at a specific index from a Dictionary in Swift?
...ctionary.keys[index]
Another possible solution would be to initialize an array with keys as input, then you can use integer subscripts on the result:
let firstKey = Array(myDictionary.keys)[0] // or .first
Remember, dictionaries are inherently unordered, so don't expect the key at a given index...
How do I access an access array item by index in handlebars?
I am trying to specify the index of an item in an array within a handlebars template:
9 Answers
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Array include any value from another array?
What's the most efficient way to test if an array contains any element from a second array?
5 Answers
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Last non-empty cell in a column
...blank cells, i.e., it will return the last non-blank cell.
It needs to be array-entered, meaning that you press Ctrl-Shift-Enter after you type or paste it in. The below is for column A:
=INDEX(A:A,MAX((A:A<>"")*(ROW(A:A))))
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How do I search within an array of hashes by hash values in ruby?
I have an array of hashes, @fathers.
4 Answers
4
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What's the $unwind operator in MongoDB?
...this is bad" }
],
other : { foo : 5 }
}
Notice how tags is actually an array of 3 items, in this case being "fun", "good" and "fun".
What $unwind does is allow you to peel off a document for each element and returns that resulting document.
To think of this in a classical approach, it would be ...
Is PHP's count() function O(1) or O(n) for arrays?
Does count() really count the all the elements of a PHP array, or is this value cached somewhere and just gets retrieved?
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