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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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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
add a comment
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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...
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...
What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
...declared as:
byte[] array = new byte[4];
You can access this array from 0 to 3, values outside this range will cause IndexOutOfRangeException to be thrown. Remember this when you create and access an array.
Array Length
In C#, usually, arrays are 0-based. It means that first element has index 0...