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What's the best manner of implementing a social activity stream? [closed]
...a social activity stream (Facebook is the most famous example). Problems/challenges involved are:
13 Answers
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How do I make a list of data frames?
...to your question, but you want to use = and not <- within the function call. If you use <-, you'll end up creating variables y1 and y2 in whatever environment you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2 <- c(4, 5, 6))
y1
# [1] 1 2 3
y2
# [1] 4 5 6
This won't have the s...
Create a .txt file if doesn't exist, and if it does append a new line
... come i wont see that before? Damn... I felt like a total dumb thanks. I really preciate these kinda good answers.
– Berker Yüceer
Mar 28 '12 at 13:07
7
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Copy files without overwrite
I just can't seem to find a way on the command line to say "copy all the files from directory A to directory B, but if the file already exists in directory B, don't overwrite it, no matter which file is newer, and don't prompt me."
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What to return if Spring MVC controller method doesn't return value?
I am using jQuery's $.getJSON() to make asynchronous calls to my simple Spring MVC backend. Most of the Spring controller methods look like this:
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How to upgrade Eclipse for Java EE Developers?
Is there any non-painful way to upgrade an Eclipse installation? I have tried browsing the eclipse site but I cannot find an useful description.
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Best way to convert strings to symbols in hash
What's the (fastest/cleanest/straightforward) way to convert all keys in a hash from strings to symbols in Ruby?
31 Answers...
What is an API key? [closed]
... further verify the origin and to prevent tampering with the values.
Typically, if you can identify the source of a request positively, it acts as a form of authentication, which can lead to access control. For example, you can restrict access to certain API actions based on who's performing the re...
jQuery: Check if div with certain class name exists
Using jQuery I'm programmatically generating a bunch of div 's like this:
18 Answers
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XML Schema (XSD) validation tool? [closed]
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After some research, I think the best answer is Xerces, as it implements all of XSD, is cross-platform and widely used. I've created a small Java project on github to validate from the command line using the default JRE parser, which is normally Xerces. This can be used on Windows/Mac/Linux.
The...