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javascript: recursive anonymous function?
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answered Oct 7 '10 at 16:46
PointyPointy
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How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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Is R's apply family more than syntactic sugar?
... n < 2 ) n
+ else fibo(n-1) + fibo(n-2)
+ }
> system.time(for(i in 0:26) fibo(i))
user system elapsed
7.48 0.00 7.52
> system.time(sapply(0:26, fibo))
user system elapsed
7.50 0.00 7.54
> system.time(lapply(0:26, fibo))
user system elapsed
7.48 ...
What is the GAC in .NET?
...s\assembly
C:\Windows\assembly>dir
Directory of C:\Windows\assembly
07/20/2009 02:18 PM <DIR> GAC
06/17/2009 04:22 PM <DIR> GAC_32
06/17/2009 04:22 PM <DIR> GAC_64
06/17/2009 04:22 PM <DIR> GAC_MSIL
...snip...
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How do write IF ELSE statement in a MySQL query
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150
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when...
Difference between MEAN.js and MEAN.io
...response!
– CMPSoares
Apr 22 '14 at 0:08
7
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Peak memory usage of a linux/unix process
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20 Answers
20
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How to check whether a pandas DataFrame is empty?
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505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...
SQL keys, MUL vs PRI vs UNI
...at column.
– pgoetz
Aug 7 '19 at 16:07
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What does the constant 0.0039215689 represent?
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0.0039215689 is approximately equal to 1/255.
Seeing that this is OpenGL, performance is probably important. So it's probably safe to guess that this was done for performance reasons.
Multiplying by the reciprocal is faster...