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How do you round a floating point number in Perl?

.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest route. printf("%.3f", 3.1415926535); # prints 3.142 The POSIX module (part of the standard Perl distribution) implements ceil(), floor(), and a number of other mathematical and trigonometric func...
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What is the difference between typeof and instanceof and when should one be used vs. the other?

... @Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/… – Colin D ...
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How do I get only directories using Get-ChildItem?

I'm using PowerShell 2.0 and I want to pipe out all the subdirectories of a certain path. The following command outputs all files and directories, but I can't figure out how to filter out the files. ...
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sizeof single struct member in C

... char text[member_size(Parent, text)]; int used; } Child; I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a constant expression. Cool stuff. share | impr...
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How to reshape data from long to wide format

... The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
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Random String Generator Returning Same String [duplicate]

...om instance in the method, which causes it to return the same values when called in quick succession. I would do something like this: private static Random random = new Random((int)DateTime.Now.Ticks);//thanks to McAden private string RandomString(int size) { StringBuilder builder = new...
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How do I find which program is using port 80 in Windows? [duplicate]

... Then you either need to watch through list carefully or install some additional software. technet.microsoft.com/en-us/sysinternals/bb897437.aspx for example. – n0rd Dec 25 '09 at 8:14 ...
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List of special characters for SQL LIKE clause

What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause? ...
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How to tell if a tag failed to load

I'm dynamically adding <script> tags to a page's <head> , and I'd like to be able to tell whether the loading failed in some way -- a 404, a script error in the loaded script, whatever. ...
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How to check whether a variable is a class or not?

... The inspect.isclass is probably the best solution, and it's really easy to see how it's actually implemented def isclass(object): """Return true if the object is a class. Class objects provide these attributes: __doc__ documentation string __module__ ...