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Pandas - How to flatten a hierarchical index in columns

... would be to set the columns to the top level: df.columns = df.columns.get_level_values(0) Note: if the to level has a name you can also access it by this, rather than 0. . If you want to combine/join your MultiIndex into one Index (assuming you have just string entries in your columns) you cou...
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How can I check for Python version in a program that uses new language features?

...oesn't have ternary Also, with is available in Python 2.5, just add from __future__ import with_statement. EDIT: to get control early enough, you could split it into different .py files and check compatibility in the main file before importing (e.g. in __init__.py in a package): # __init__.py #...
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Determine if variable is defined in Python [duplicate]

...() if you want to be pedantic, you can check the builtins too 'a' in vars(__builtins__) share | improve this answer | follow | ...
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Any reason not to use '+' to concatenate two strings?

...ucture, especially if it is growing. With list you can use list.extend(list_of_items) and list.append(item) which are much faster when concatenating stuff dynamically. – Antti Haapala Sep 11 '12 at 9:56 ...
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Test if a variable is a list or tuple

... How about: hasattr(a, "__iter__") ? It tells if the object returned can be iterated over as a generator. By default, tuples and lists can, but not the string types. share...
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PowerShell script to return versions of .NET Framework on a machine?

...up\NDP' -recurse | Get-ItemProperty -name Version,Release -EA 0 | Where { $_.PSChildName -match '^(?!S)\p{L}'} | Select PSChildName, Version, Release Based on the MSDN article, you could build a lookup table and return the marketing product version number for releases after 4.5: $Lookup = @{ ...
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define() vs. const

... a static scalar (number, string or other constant like true, false, null, __FILE__), whereas define() takes any expression. Since PHP 5.6 constant expressions are allowed in const as well: const BIT_5 = 1 << 5; // Valid since PHP 5.6 and invalid previously define('BIT_5', 1 << 5); /...
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How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?

... You could put a _ViewStart.cshtml file inside the /Views/Public folder which would override the default one in the /Views folder and specify the desired layout: @{ Layout = "~/Views/Shared/_PublicLayout.cshtml"; } By analogy you could...
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The most accurate way to check JS object's type?

... constructor: Native Type Ex1: var string1 = "Test"; console.log(string1.__proto__.constructor.name); displays: String Ex2: var array1 = []; console.log(array1.__proto__.constructor.name); displays: Array Custom Classes: function CustomClass(){ console.log("Custom Class Object C...
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Can I query MongoDB ObjectId by date?

...cuments created after midnight on May 25th, 1980 */ db.mycollection.find({ _id: { $gt: objectIdWithTimestamp('1980/05/25') } }); share | improve this answer | follow ...