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Adding a new array element to a JSON object

...Object, then stringify back to JSON var jsonStr = '{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}'; var obj = JSON.parse(jsonStr); obj['theTeam'].push({"teamId":"4","status":"pending"}); jsonStr = JSON.stringify(obj); // "{"theTeam...
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Cost of len() function

... It's O(1) (constant time, not depending of actual length of the element - very fast) on every type you've mentioned, plus set and others such as array.array. ...
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Selecting with complex criteria from pandas.DataFrame

...; from random import randint >>> df = pd.DataFrame({'A': [randint(1, 9) for x in range(10)], 'B': [randint(1, 9)*10 for x in range(10)], 'C': [randint(1, 9)*100 for x in range(10)]}) >>> df A B C 0 9 40 300 1 9 70 700 2 5 70 90...
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Why do enum permissions often have 0, 1, 2, 4 values?

Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ? 7 Answers ...
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How to convert list of key-value tuples into dictionary?

...p and zip it. ValueError: dictionary update sequence element #0 has length 1916; 2 is required THAT is your actual question. The answer is that the elements of your list are not what you think they are. If you type myList[0] you will find that the first element of your list is not a two-tuple, e....
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How to join two sets in one line without using “|”

... | edited Jun 26 '17 at 12:03 Rishabh Agrahari 2,22311 gold badge1616 silver badges1919 bronze badges ...
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How to randomize (or permute) a dataframe rowwise and columnwise?

I have a dataframe (df1) like this. 8 Answers 8 ...
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How do you plot bar charts in gnuplot?

... 124 Simple bar graph: set boxwidth 0.5 set style fill solid plot "data.dat" using 1:3:xtic(2) w...
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Build vs new in Rails 3

...enrym:~/testapp$ rails c Loading development environment (Rails 3.0.4) r:001 > (some_firm = Firm.new).save # Create and save a new Firm #=> true r:002 > some_firm.clients # No clients yet #=> [] r:003 > some_firm.clients.new # Create a new client #=> #<Client i...
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Why does direction of index matter in MongoDB?

... 114 MongoDB concatenates the compound key in some way and uses it as the key in a BTree. When fin...