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Adding new column to existing DataFrame in Python pandas

...17438 0.847941 0.034235 -0.448948 2.228131 >>> p.version.short_version '0.16.1' The SettingWithCopyWarning aims to inform of a possibly invalid assignment on a copy of the Dataframe. It doesn't necessarily say you did it wrong (it can trigger false positives) but from 0.13.0 it let yo...
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Why would finding a type's initializer throw a NullReferenceException?

....cs: (196c.1874): Access violation - code c0000005 (first chance) mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3: 000007fe`e5735403 488b4608 ...
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How do I get the different parts of a Flask request's url?

...ributes would be the following: path /page.html script_root /myapplication base_url http://www.example.com/myapplication/page.html url http://www.example.com/myapplication/page.html?x=y url_root http://www.example.com/myapplication/ ...
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What exactly are late static bindings in PHP?

...self::, parent::, static::, or, if going up in the class hierarchy, forward_static_call(). The function get_called_class() can be used to retrieve a string with the name of the called class and static:: introduces its scope. ...
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Rails 3 execute custom sql query without a model

... Maybe try this: ActiveRecord::Base.establish_connection(...) ActiveRecord::Base.connection.execute(...) share | improve this answer | follow ...
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Using custom std::set comparator

...overloads the () operator so it can be called like a function). struct lex_compare { bool operator() (const int64_t& lhs, const int64_t& rhs) const { stringstream s1, s2; s1 << lhs; s2 << rhs; return s1.str() < s2.str(); } }; You then...
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A semantics for Bash scripts?

...s not terribly robust, but it is instructive: #!/usr/bin/env python from __future__ import print_function import os, sys '''Hacky barebones shell.''' try: input=raw_input except NameError: pass def main(): while True: cmd = input('prompt> ') args = cmd.split() if not args: ...
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Do I need dependency injection in NodeJS, or how to deal with …?

...nnection.js: (be sure to choose a better name) var db = require('whichever_db_vendor_i_use'); module.exports.fetchConnection() = function() { //logic to test connection //do I want to connection pool? //do I need only one connection throughout the lifecyle of my application? ret...
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Replace only some groups with Regex

...attern = @"-(\d+)-"; var replaced = Regex.Replace(text, pattern, (_match) => { Group group = _match.Groups[1]; string replace = "AA"; return String.Format("{0}{1}{2}", _match.Value.Substring(0, group.Index - _match.Index), replace, _match.Value...
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Does Dart support enumerations?

...old approach before 1.8: class Fruit { static const APPLE = const Fruit._(0); static const BANANA = const Fruit._(1); static get values => [APPLE, BANANA]; final int value; const Fruit._(this.value); } Those static constants within the class are compile time constants, and this cl...