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std::string to float or double
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The Standard Library (C++11) offers the desired functionality with std::stod :
std::string s = "0.6"
std::wstring ws = "0.7"
double d = std::stod(s);
double dw = std::stod(ws);
Generally for most other basic types, see <st...
How can I view the source code for a function?
...S4 method dispatch system
The S4 system is a newer method dispatch system and is an alternative to the S3 system. Here is an example of an S4 function:
> library(Matrix)
Loading required package: lattice
> chol2inv
standardGeneric for "chol2inv" defined from package "base"
function (x, ...)...
Is PowerShell ready to replace my Cygwin shell on Windows? [closed]
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They help or they don't.
You need help or you don't.
If you know Unix and those tools do what you need them to do on Windows - then you are a happy guy and there is no need to learn PowerShell (unless you want to explore).
My original intent was to include a set of Unix tools in Windows and be...
Vagrant error: NFS is reporting that your exports file is invalid
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Try using the known good versions of VirtualBox and Vagrant noted in Discourse as Your First Rails App:
Vagrant 1.1.2
VirtualBox 4.2.10
I was having the same issue on Mac (OS X 10.9 (Mavericks)), but rolling back to these versions seemed to fix it for me.
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max value of integer
In C, the integer (for 32 bit machine) is 32 bits, and it ranges from -32,768 to +32,767.
In Java, the integer(long) is also 32 bits, but ranges from -2,147,483,648 to +2,147,483,647.
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Does Spring @Transactional attribute work on a private method?
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The Question is not private or public, the question is: How is it invoked and which AOP implementation you use!
If you use (default) Spring Proxy AOP, then all AOP functionality provided by Spring (like @Transactional) will only be taken into account if the call goes through the proxy. -- This is n...
How to parse JSON in Java
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I agree with @StaxMan. I just tried org.json and it's horribly cumbersome. It really doesn't play with with standard Java Collection types, for example.
– Ken Williams
Nov 12 '14 at 16:55
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Remove the last line from a file in Bash
...sed.
MacOS:
On Mac OS X (as of 10.7.4), the equivalent of the sed -i command above is
sed -i '' -e '$ d' foo.txt
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Delete directories recursively in Java
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It's a little more thorough. It handles things like symbolic links correctly on Linux/Unix. svn.apache.org/viewvc/commons/proper/io/trunk/src/java/org/…
– Steve K
Apr 22 '09 at 22:48
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PostgreSQL: Is it better to use multiple databases with one schema each, or one database with multip
... will work with no trouble. So you definitely want to go with one database and multiple schemas within that database.
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