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How to get the last N rows of a pandas DataFrame?

... dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') : 3 Answers ...
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How do I write data into CSV format as string (not file)?

... I found the answers, all in all, a bit confusing. For Python 2, this usage worked for me: import csv, io def csv2string(data): si = io.BytesIO() cw = csv.writer(si) cw.writerow(data) return si.getvalue().strip('\r\n') data=[1,2...
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Setup RSpec to test a gem (not Rails)

...my_gem ) to setup the structure for the new gem and edit the *.gemspec manually. I also added s.add_development_dependency "rspec", ">= 2.0.0" to gemspec and did a bundle install . ...
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JavaScript: Class.method vs. Class.prototype.method

... are extending the constructor function prototype, it will be available to all the object instances created with the new keyword, and the context within that function (the this keyword) will refer to the actual object instance where you call it. Consider this example: // constructor function funct...
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How to fix the uninitialized constant Rake::DSL problem on Heroku?

...ixed my problems and I didn't know what was going on. (Using the rails installer on windows and deploying to heroku, as a complete beginner.) – Jack V. Jun 14 '11 at 22:46 1 ...
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Determine if an object property is ko.observable

...ce) { if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false; if (instance.__ko_proto__ === ko.dependentObservable) return true; return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain }; UPDATE: If you are using KO 2...
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How does one generate a random number in Apple's Swift language?

... introduces new easy-to-use random functions for many data types. You can call the random() method on numeric types. let randomInt = Int.random(in: 0..<6) let randomDouble = Double.random(in: 2.71828...3.14159) let randomBool = Bool.random() ...
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How can I split and parse a string in Python?

I am trying to split this string in python: 2.7.0_bf4fda703454 3 Answers 3 ...
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How to copy an object in Objective-C

...deep, logical copy. In this, we make a copy of the object, but without actually doing it bit by bit - we want an object that behaves the same for all intents and purposes, but isn't (necessarily) a memory-identical clone of the original - the Objective C manual calls such an object "functionally ind...
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Changing the cursor in WPF sometimes works, sometimes doesn't

...deCursor: Mouse.OverrideCursor = Cursors.Wait; try { // do stuff } finally { Mouse.OverrideCursor = null; } This overrides the cursor for your application rather than just for a part of its UI, so the problem you're describing goes away. ...