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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...
...
How do write IF ELSE statement in a MySQL query
...
150
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when...
Peak memory usage of a linux/unix process
...
20 Answers
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Difference between MEAN.js and MEAN.io
...response!
– CMPSoares
Apr 22 '14 at 0:08
7
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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?
...
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...
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(...
Putting text in top left corner of matplotlib plot
...t is in data coords,
alternatively, you can specify text in axis coords (0,0 is lower-left
and 1,1 is upper-right). The example below places text in the center
of the axes::
text(0.5, 0.5,'matplotlib',
horizontalalignment='center',
verticalalignment='center',
transform = ax.t...
Index all *except* one item in python
.... For example, to make b a copy of a without the 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays. If y...