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How can I find the first occurrence of a sub-string in a python string?
... knowledge: rfind and rindex:
In general, find and index return the smallest index where the passed-in string starts, and rfind and rindex return the largest index where it starts
Most of the string searching algorithms search from left to right, so functions starting with r indicate that the...
How to succinctly write a formula with many variables from a data frame?
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There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but...
How can I get a JavaScript stack trace when I throw an exception?
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Edit 2 (2017):
In all modern browsers you can simply call: console.trace(); (MDN Reference)
Edit 1 (2013):
A better (and simpler) solution as pointed out in the comments on the original question is to use the stack property of an Error objec...
What is the difference between git clone and checkout?
... operates on data that's already fetched. So it's not like svn checkout at all.
– August Lilleaas
May 26 '15 at 12:02
13
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Record file copy operation with Git
...n (-C implies -M), and you can request more expensive copy detection among all files with --find-copies-harder or -C -C (which implies -C, which implies -M). See the git-diff manpage.
You can also configure git to always do rename detection by setting diff.renames to a boolean true value (e.g. true...
JRuby on Rails vs. Ruby on Rails, what's difference?
...hem from within Ruby code with JRuby. In the other direction you can also call JRuby code from within Java. JRuby can also use the JVM and application server capabilities.
JRuby is usually hosted within Java application servers such as Sun's GlassFish or even the Tomcat web server.
Although you cann...
What is the smallest possible valid PDF?
Out of simple curiosity, having seen the smallest GIF , what is the smallest possible valid PDF file?
4 Answers
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Why is LINQ JOIN so much faster than linking with WHERE?
...ite efficient because the DB knows how to perform a join. But it doesn't really make sense to compare it with the other approaches, since they work directly in memory (Linq to DataSet)
The query with multiple tables and a Where condition actually performs a cartesian product of all the tables, then ...
What does the tilde before a function name mean in C#?
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~ is the destructor
Destructors are invoked automatically, and cannot be invoked explicitly.
Destructors cannot be overloaded. Thus, a class can have, at most, one destructor.
Destructors are not inherited. Thus, a class has no destructors other than the one, which may be decla...
Is it OK to use Gson instance as a static field in a model bean (reuse)?
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According to the comments the existing unit test does not really test much, be careful with anything related to thread safety...
There is a unit test checking for thread safety:
/**
* Tests for ensuring Gson thread-safety.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
pu...