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How do I create a SHA1 hash in ruby?
... of ruby. Worse yet, the string being passed to hexdigest isn't dynamic at all! This method would return the same hash regardless what data you give it!
– Blixxy
Jul 7 '12 at 10:10
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python numpy machine epsilon
...s of Python's builtin float. Python floats are 64-bit (C double) on almost all platforms. float and np.float64 therefore usually have equivalent precision, and for most purposes you can use them interchangeably. However they aren't identical - np.float64 is a numpy-specific type, and an np.float64 s...
Why can't radio buttons be “readonly”?
...the value (or does it?), and it grays out the radio button. Read-only is really what I'm looking for, but for some mysterious reason it doesn't work.
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How do I get the MAX row with a GROUP BY in LINQ query?
... (s => s.uid, tv => tv.uid, asdf => asdf.uid). Linq will automatically recognize it as selecting over elements of type Serial.
– Michael
Mar 17 '11 at 17:03
add a com...
ROW_NUMBER() in MySQL
...mmonly-asked SQL questions (since it seems like it should be easy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the...
Could not load file or assembly 'System.Data.SQLite'
I've installed ELMAH 1.1 .Net 3.5 x64 in my ASP.NET project and now I'm getting this error (whenever I try to see any page):
...
How do I tell matplotlib that I am done with a plot?
...
You can use plt.close()/pylab.close() to remove all old figures
– Calvin1602
Jan 24 '13 at 8:32
2
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Why do table names in SQL Server start with “dbo”?
At least on my local instance, when I create tables, they are all prefixed with "dbo.". Why is that?
3 Answers
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Why is the standard session lifetime 24 minutes (1440 seconds)?
...P3 days, PHP itself had no session support.
But an open-source library called PHPLIB, initially written by Boris Erdmann and Kristian Koehntopp from NetUSE AG, provided sessions via PHP3 code.
Session lifetimes were defined in minutes, not seconds. And the default lifetime was 1440 minutes, o...
How to sort the letters in a string alphabetically in Python
Is there an easy way to sort the letters in a string alphabetically in Python?
7 Answers
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