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TCP: can two different sockets share a port?
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A server socket listens on a single port. All established client connections on that server are associated with that same listening port on the server side of the connection. An established connection is uniquely identified by the combination of client-side and serv...
list every font a user's browser can display
Is there a way in javascript to obtain the names of all fonts (or font-families) that the browser can show? (I want to give the user a dropdown with a list of all available fonts, and allow the user to choose a font.)
I'd prefer not to have to hardcode this list ahead of time or send it down from t...
How do I set the version information for an existing .exe, .dll?
As part of our build process I need to set the version information for all of our compiled binaries. Some of the binaries already have version information (added at compile time) and some do not.
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How to convert a string to an integer in JavaScript?
... and you want an integer:
var x = Math.floor("1000.01"); //floor automatically converts string to number
or, if you're going to be using Math.floor several times:
var floor = Math.floor;
var x = floor("1000.01");
If you're the type who forgets to put the radix in when you call parseInt, you ca...
Detect and exclude outliers in Pandas data frame
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If you have multiple columns in your dataframe and would like to remove all rows that have outliers in at least one column, the following expression would do that in one shot.
df = pd.DataFrame(np.random.randn(100, 3))
from scipy import stats
df[(np.abs(stats.zscore(df)) < 3).all(axis=1)]
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What is the meaning of the term arena in relation to memory?
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An arena is just a large, contiguous piece of memory that you allocate once and then use to manage memory manually by handing out parts of that memory. For example:
char * arena = malloc(HUGE_NUMBER);
unsigned int current = 0;
void * my_malloc(size_t n) { current += n; return arena +...
What's the difference between git clone --mirror and git clone --bare
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The difference is that when using --mirror, all refs are copied as-is. This means everything: remote-tracking branches, notes, refs/originals/* (backups from filter-branch). The cloned repo has it all. It's also set up so that a remote update will re-fetch everything f...
Why is using the rails default_scope often recommend against?
...to show unpublished (private) posts. So far so good.
2.1.1 :001 > Post.all
Post Load (0.2ms) SELECT "posts".* FROM "posts" WHERE "posts"."published" = 't'
Well this is pretty much what we expect. Now lets try:
2.1.1 :004 > Post.new
=> #<Post id: nil, title: nil, published: true...
Some questions about Automatic Reference Counting in iOS5 SDK
...k will be completed) for iOS 4.3.
I just read about ARC in iOS 5, and basically I understood that we will never need to release and retain objects anymore. My questions are:
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Why does Double.NaN==Double.NaN return false?
...enormalized value or a signed zero, and an operation that has no mathematically definite result produces NaN. All numeric operations with NaN as an operand produce NaN as a result. As has already been described, NaN is unordered, so a numeric comparison operation involving one or two NaNs returns fa...