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remove None value from a list without removing the 0 value
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>>> L = [0, 23, 234, 89, None, 0, 35, 9]
>>> [m>x m> for m>x m> in L if m>x m> is not None]
[0, 23, 234, 89, 0, 35, 9]
Just for fun, here's how you can adapt filter to do this without using a lambda, (I wouldn't recommend this code - it's just for scientific purposes)
>>> f...
How do I change the value of a global variable inside of a function
...That's why it's considered best practice to always declare your variables em>x m>plicitly with var. Because if you forget it, you can start messing with globals by accident. It's an easy mistake to make. But in your case, this turn around and becomes an easy answer to your question.
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How can I read inputs as numbers?
Why are m>x m> and y strings instead of ints in the below code?
10 Answers
10
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Pan & Zoom Image
....RenderTransform;
double zoom = e.Delta > 0 ? .2 : -.2;
st.Scalem>X m> += zoom;
st.ScaleY += zoom;
}
To handle the panning the first thing I did was to handle the MouseLeftButtonDown event on the image, to capture the mouse and to record it's location, I also store the current value of t...
Unable to load DLL 'SQLite.Interop.dll'
Periodically I am getting the following em>x m>ception:
41 Answers
41
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Alternate output format for psql
...t needed to spend more time staring at the documentation. This command:
\m>x m> on
will do em>x m>actly what I wanted. Here is some sample output:
select * from dda where u_id=24 and dda_is_deleted='f';
-[ RECORD 1 ]------+---------------------------------------------------------------------------------...
Checking for empty arrays: count vs empty
...s simply that something that should have happened, didn't happen: the non-em>x m>istence of the member variable in the subclass was treated em>x m>actly the same way as though this member variable, an array, was empty — i.e., as though it had no elements). This is problematic, and another em>x m>ample of PHP bei...
What's the fastest way to merge/join data.frames in R?
For em>x m>ample (not sure if most representative em>x m>ample though):
5 Answers
5
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How to convert strings into integers in Python?
...ins lists, only one level), you could do this in Python 2:
T2 = [map(int, m>x m>) for m>x m> in T1]
In Python 3:
T2 = [list(map(int, m>x m>)) for m>x m> in T1]
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How to convert a factor to integer\numeric without loss of information?
...nd may
happen by implicit coercion. To
transform a factor f to
approm>x m>imately its original numeric
values, as.numeric(levels(f))[f] is
recommended and slightly more
efficient than
as.numeric(as.character(f)).
The FAQ on R has similar advice.
Why is as.numeric(levels(f))[f] more ef...