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Accessing dict_keys element by index in Python3
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Call list() on the dictionary instead:
keys = list(test)
In Python 3, the dict.keys() method returns a dictionary view object, which acts as a set. Iterating over the dictionary directly also yields keys, so turning a dictionary into a list results in a list of all the keys:
>>> te...
Retrieve only the queried element in an object array in MongoDB collection
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db.test.find({"shapes.color": "red"}, {_id: 0, 'shapes.$': 1});
MongoDB 3.2 Update
Starting with the 3.2 release, you can use the new $filter aggregation operator to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggrega...
Get list from pandas DataFrame column headers
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edited Apr 3 '19 at 9:51
cs95
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Listing all permutations of a string/integer
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I found the pseudocode on http://www.programmersheaven.com/mb/Algorithms/369713/369713/permutation-algorithm-help/:
makePermutations(permutation) {
if (length permutation < required length) {
for (i = min digit to max digit) {
if (i not in permutation) {
makePermutations(per...
Get value of dynamically chosen class constant in PHP
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Brad
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answered May 27 '11 at 2:20
Dan SimonDan Sim...
How to detect the currently pressed key?
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163
if ((Control.ModifierKeys & Keys.Shift) != 0)
This will also be true if Ctrl+Shift is dow...
T-SQL stored procedure that accepts multiple Id values
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237
Erland Sommarskog has maintained the authoritative answer to this question for the last 16 year...
How to overcome root domain CNAME restrictions?
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63
The reason this question still often arises is because, as you mentioned, somewhere somehow some...