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How to select where ID in Array Rails ActiveRecord without exception

...ore relevant for Rails 4.x Do this: current_user.comments.where(:id=>[123,"456","Michael Jackson"]) The stronger side of this approach is that it returns a Relation object, to which you can join more .where clauses, .limit clauses, etc., which is very helpful. It also allows non-existent IDs ...
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How to generate all permutations of a list?

... Combination (order does NOT matter): print list(itertools.combinations('123', 2)) [('1', '2'), ('1', '3'), ('2', '3')] Cartesian product (with several iterables): print list(itertools.product([1,2,3], [4,5,6])) [(1, 4), (1, 5), (1, 6), (2, 4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)] Cartesia...
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http HEAD vs GET performance

...EAD might work nicely. For example, suppose you want to check if resource 123 exists. A 200 means "yes" and a 404 means "no": HEAD /resources/123 HTTP/1.1 [...] HTTP/1.1 404 Not Found [...] However, if the "yes" or "no" you want from your REST service is a part of the resource itself, rather th...
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Why can't variable names start with numbers?

... If it had to be numbers+alpha, then you could still do String 0x123 = "Hello World". Unless you state that variable names are "numbers+alpha that don't parse to a valid numeric designation", and that's just silly. – eaolson Oct 11 '09 at 3:56 ...
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Strangest language feature

... Or, more usefully, "0123456789abcdef"[x & 0xf] – Dipstick Jan 3 '10 at 15:33 17 ...
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How to insert a character in a string at a certain position?

...but was suggested to use String for a better display output (instead of 1234.5 will be 1234.50 ). Therefore, I need a function that will take an int as parameter and return the properly formatted String with a decimal point 2 digits from the end. ...
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Map vs Object in JavaScript

...d Symbol keys where as Maps support more or less any key type. If I do obj[123] = true and then Object.keys(obj) then I will get ["123"] rather than [123]. A Map would preserve the type of the key and return [123] which is great. Maps also allow you to use Objects as keys. Traditionally to do this y...
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Matplotlib - Move X-Axis label downwards, but not X-Axis Ticks

...red Jul 29 '14 at 14:57 Matthias123Matthias123 79266 silver badges1313 bronze badges ...
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How to convert index of a pandas dataframe into a column?

... df1 = pd.DataFrame({"gi":[232,66,34,43],"ptt":[342,56,662,123]}) p = df1.index.values df1.insert( 0, column="new",value = p) df1 new gi ptt 0 0 232 342 1 1 66 56 2 2 34 662 3 3 43 123 ...
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How do I create a readable diff of two spreadsheets using git diff?

...sxd OpenOffice.org .odt/.ods/.odp/.odg Open Document .wj2/wj3/wk3/wk4/123 Lotus 123 .wri Windows3.1 Write .pdf Adobe PDF .mht Web Archive .eml Exported files from OutlookExpress Regard, Andres share ...