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Convert a list of data frames into one data frame
...ession:
R version 3.3.0 (2016-05-03)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1
> packageVersion("plyr")
[1] ‘1.8.4’
> packageVersion("dplyr")
[1] ‘0.5.0’
> packageVersion("data.table")
[1] ‘1.9.6’
UPDATE:
Rerun 31-J...
How to install psycopg2 with “pip” on Python?
...
Note: Since a while back, there are binary wheels for Windows in PyPI, so this should no longer be an issue for Windows users. Below are solutions for Linux, Mac users, since lots of them find this post through web searches.
Option 1
Install the psycopg2-binary PyPI package ...
Error to run Android Studio
..."
Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)
Check what compiler is used
javac -version
It should show something like this
javac 1.8.0_91
Finally, add JAVA_HOME to the environment variable
Edit /etc/environment and ad...
Is there a max array length limit in C++?
...support in the integer math unit. On every x86 OS I've used, size_t is 32-bits for a 32-bit OS and 64-bits for a 64-bit OS.
– Mr Fooz
Dec 18 '09 at 22:36
2
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Real differences between “java -server” and “java -client”?
...h a much smaller kernel.
G. Demecki points out in the comments that in 64-bit versions of JDK, the -client option is ignored for many years.
See Windows java command:
-client
Selects the Java HotSpot Client VM.
A 64-bit capable JDK currently ignores this option and instead uses the Java Hotspot S...
How to convert std::string to LPCSTR?
...u can ignore the L (long) part of the names -- it's a holdover from 16-bit Windows.
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
...h they are cached. In my experience the query cache isn't often a very big win anyway. Queries and schemas need special construction to make maximum use of the cache. Often application-level caching ends up being necessary anyway in the long run.
Native prepares doesn't make any difference for secur...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...ve some integer n, and I want to know the position of the most significant bit (that is, if the least significant bit is on the right, I want to know the position of the furthest left bit that is a 1), what is the quickest/most efficient method of finding out?
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What does #defining WIN32_LEAN_AND_MEAN exclude exactly?
I found the explanation defining WIN32_LEAN_AND_MEAN "reduces the size of the Win32 header files by excluding some of the less frequently used APIs". Somewhere else I read that it speeds up the build process.
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Android SDK on a 64-bit linux machine
Is it possible to develop using the Android SDK on a 64-bit linux machine. The available SDK downloads seem to be just for 32-bit versions of Linux.
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