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What is the difference between join and merge in Pandas?

... I always use join on indices: import pandas as pd left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key') right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key') left.join(right, lsuffix='_l', rsuffix='_r') val_l ...
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Random date in C#

I'm looking for some succinct, modern C# code to generate a random date between Jan 1 1995 and the current date. 7 Answers ...
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Truncating floats in Python

... First, the function, for those who just want some copy-and-paste code: def truncate(f, n): '''Truncates/pads a float f to n decimal places without rounding''' s = '{}'.format(f) if 'e' in s or 'E' in s: return '{0:.{1}f}'.format(f, n) i, p, d = s.partitio...
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Convert to/from DateTime and Time in Ruby

How do you convert between a DateTime and a Time object in Ruby? 6 Answers 6 ...
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nginx showing blank PHP pages

..._errors in php.ini but no luck. php5-fpm.log is not producing any errors and neither is nginx. 17 Answers ...
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Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?

...lPlaces + "} {1}", adjustedSize, SizeSuffixes[mag]); } And here's the original implementation I suggested, which may be marginally slower, but a bit easier to follow: static readonly string[] SizeSuffixes = { "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", ...
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Why don't C++ compilers define operator== and operator!=?

...ison or a deep (internal) comparison. It's safer to just not implement it and let the programmer do that themselves. Then they can make all the assumptions they like. share | improve this answer ...
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Javascript array search and remove string?

... = ['A', 'B', 'C', 'B']; t.splice(t.indexOf('B'), 1); // will return ['B'] and t is now equal to ['A', 'C', 'B'] share | improve this answer | follow | ...
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What's the difference between a web site and a web application? [closed]

I'm stumped trying to come up to a difference between a website and a web application for myself. As I see it, a web site points to a specific page and a web application is more of some sort of 'portal' to content and information. ...
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How to delete a row by reference in data.table?

...estion. data.table can't delete rows by reference yet. data.table can add and delete columns by reference since it over-allocates the vector of column pointers, as you know. The plan is to do something similar for rows and allow fast insert and delete. A row delete would use memmove in C to budge u...