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boost::flat_map and its performance compared to map and unordered_map

...erformance a lot due to cache hits. I recently found out about boost::flat_map which is a vector based implementation of a map. It doesn't seem to be nearly as popular as your typical map / unordered_map so I haven't been able to find any performance comparisons. How does it compare and what are...
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How do I calculate square root in Python?

...ethod can be computed as: sqrt = x**(float(1)/2) – VM_AI Sep 28 '18 at 10:41 add a comment  |  ...
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Getting SyntaxError for print with keyword argument end=' '

I have this python script where I need to run gdal_retile.py , but I get an exception on this line: 14 Answers ...
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Git - How to use .netrc file on Windows to save user and password

...onment variable %HOME% (pre-Git 2.0, no longer needed with Git 2.0+) put a _netrc file in %HOME% If you are using Windows 7/10, in a CMD session, type: setx HOME %USERPROFILE% and the %HOME% will be set to 'C:\Users\"username"'. Go that that folder (cd %HOME%) and make a file called '_netrc' N...
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If isset $_POST

... Since !empty() is already checks for both, you can use this: if (!empty($_POST["mail"])) { echo "Yes, mail is set"; } else { echo "No, mail is not set"; } share | improve this answe...
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Can someone explain __all__ in Python?

I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files. Can someone explain what this does? ...
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How to import the class within the same directory or sub directory?

... Python 2 Make an empty file called __init__.py in the same directory as the files. That will signify to Python that it's "ok to import from this directory". Then just do... from user import User from dir import Dir The same holds true if the files are in a...
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javac : command not found

... yes, i am sure. just look at the java-1.6.0-openjdk.x86_64 package information (scroll to the "Files" section) and see that there is no javac in that package. and then look at the OpenJDK Development Environment package. – ax. Mar 23 '11 at ...
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How do I filter query objects by date range in Django?

... Use Sample.objects.filter(date__range=["2011-01-01", "2011-01-31"]) Or if you are just trying to filter month wise: Sample.objects.filter(date__year='2011', date__month='01') Edit As Bernhard Vallant said, if you want a query...
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FragmentPagerAdapter Exists Only In Android.Support.V4.App (and not Android.App)

...pp.Fragment; namespace Support4 { [Activity (Label = "@string/fragment_pager_support")] [IntentFilter (new[]{Intent.ActionMain}, Categories = new[]{ "mono.support4demo.sample" })] public class FragmentPagerSupport : Activity //public class FragmentPagerSupport : FragmentActivity ...