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Get operating system info
I recently started wondering about sites like http://thismachine.info/ that get the user's operating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure it out.
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What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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Difference between HEAD and master
What is the difference between the HEAD and master in Git?
3 Answers
3
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What are bitwise operators?
...into it in either an academic or professional setting, so stuff like these bitwise operators really escapes me.
9 Answers
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LINQ - Left Join, Group By, and Count
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from p in context.ParentTable
join c in context.ChildTable on p.ParentId equals c.ChildParentId into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != nu...
Adding days to a date in Python
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The previous answers are correct but it's generally a better practice to do:
import datetime
Then you'll have, using datetime.timedelta:
date_1 = datetime.datetime.strptime(start_date, "%m/%d/%y")
end_date = date_1 + datetime.timedelta(days=10)
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Dark theme in Netbeans 7 or 8
Is there a way to have a dark theme in Netbeans?
6 Answers
6
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Get list of passed arguments in Windows batch script (.bat)
I'd like to find a Windows batch counterpart to Bash's $@ that holds a list of all arguments passed into a script.
14 An...
What's the difference between “groups” and “captures” in .NET regular expressions?
I'm a little fuzzy on what the difference between a "group" and a "capture" are when it comes to .NET's regular expression language. Consider the following C# code:
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Java - sending HTTP parameters via POST method easily
... sent as part of the URL.
In a POST request, the parameters are sent as a body of the request, after the headers.
To do a POST with HttpURLConnection, you need to write the parameters to the connection after you have opened the connection.
This code should get you started:
String urlParameters ...