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Python string.join(list) on object array rather than string array
...riments says that the list comprehension one can be a good 60% faster on small lists (experiment run 10^6 times on a list of three object()s). However, their performance is similar on big lists (2nd experiment run once on a 10^7 objects() list).
– gozzilli
Mar ...
Fast way to discover the row count of a table in PostgreSQL
...of rows due to the nature of MVCC. There is a way to speed this up dramatically if the count does not have to be exact like it seems to be in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like ...
How to install Xcode Command Line Tools
How do I get the command-line build tools installed with the current Xcode/Mac OS X v10.8 (Mountain Lion) or later?
13 Answ...
Android studio: why are minSdkVersion and targetSdkVersion specified both in AndroidManifest.xml and
...ties and generate another apk.
You can leave the manifest as it is and do all configuration in build.gradle. You can safely remove
<uses-sdk></uses-sdk>
from manifest as well as version codes.
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What is a .pid file and what does it contain?
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Pidfile contains pid of a process. It is a convention allowing long running processes to be more self-aware. Server process can inspect it to stop itself, or have heuristic that its other instance is already running. Pidfiles can also be used to conventiently kill risk manually,...
Use of Initializers vs Constructors in Java
...hen the class is loaded, then a static initializer is the way to go, especially as it allows you to do a complex initialization and still have the static variable be final. This is a big win.
I find "if (someStaticVar == null) // do stuff" to be messy and error prone. If it is initialized statica...
When to use std::size_t?
...t you need to compare in the loop condition against something that is naturally a std::size_t itself.
std::size_t is the type of any sizeof expression and as is guaranteed to be able to express the maximum size of any object (including any array) in C++. By extension it is also guaranteed to be big...
Query EC2 tags from within instance
...the ec2-api-tools package, but I got nothing but 404's when I tried to install it.
– Edward Falk
Apr 8 '12 at 19:39
2
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How to set the style -webkit-transform dynamically using JavaScript?
... change the -webkit-transform: rotate() property using JavaScript dynamically, but the commonly used setAttribute is not working:
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How to reference the initial commit?
...nches, such as 'html', 'man' and 'todo' in git.git repository). This is usually result of joining separate projects in one, or using subtree merge of separately developed subproject.
For example git repository has 6 root commits: git-gui, gitk (subtree-merged), gitweb (merged in, no longer develop...