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How to set size for local image using knitr for markdown?
...ge that I would like to include in an .Rmd file which I will then knit and convert to HTML slides with Pandoc . Per this post , this will insert the local image :
...
How can I convert ereg expressions to preg in PHP?
...c, a backslash or a whitespace character. The most used are generally ~, / and #.
You can also use matching brackets:
preg_match('[^hello]', $str);
preg_match('(^hello)', $str);
preg_match('{^hello}', $str);
// etc
If your delimiter is found in the regular expression, you have to escape it:
ere...
Default value to a parameter while passing by reference in C++
...ifferent address to the function? or will the address of State be always 0 and so meaningless?
– Sony
Jun 29 '09 at 18:10
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When should i use npm with “-g” flag and why?
...g npm for js package management recently. Although I do have a fair understanding of package management in different enivronments(lets say using apt, rvm/gem, pythonbrew/virtualenv/pip), I don't quite understand how npm fully fits in.
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How does HashSet compare elements for equality?
..., it will find the hash code using IEqualityComparer<T>.GetHashCode, and store both the hash code and the element (after checking whether the element is already in the set, of course).
To look an element up, it will first use the IEqualityComparer<T>.GetHashCode to find the hash code, t...
Java using enum with switch statement
...about this:
Use a list of static final ints rather than a type-safe enum and switch on the int value you receive (this is the pre-Java 5 approach)
Switch on either a specified id value (as described by heneryville) or the ordinal value of the enum values; i.e. guideView.GUIDE_VIEW_SEVEN_DAY.ordina...
Change values while iterating
... prints you completely different memory locations for the value from range and the actual
value in the slice:
0xf84000f010 vs. 0x7f095ed0bf68
0xf84000f014 vs. 0x7f095ed0bf68
0xf84000f018 vs. 0x7f095ed0bf68
So the only thing you can do is to either use pointers or the index, as already proposed ...
CSS3 Continuous Rotate Animation (Just like a loading sundial)
...te an Apple style activity indicator (sundial loading icon) by using a PNG and CSS3 animation. I have the image rotating and doing it continuously, but there seems to be a delay after the animation has finished before it does the next rotation.
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Do I need to heartbeat to keep a TCP connection open?
...s that that communicate via TCP/IP. Component A acts as a server/listener and Component B is the client. The two should communicate as quickly as possible. There can only ever be one connection at any time (though that is aside to this question). A senior developer at my company has said I need ...
What is a database transaction?
... To do that you have first to withdraw the amount from the source account, and then deposit it to the destination account. The operation has to succeed in full. If you stop halfway, the money will be lost, and that is Very Bad.
In modern databases transactions also do some other things - like ensur...