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How to stop flask application without using ctrl-c
...op()" API, I am curious about how to code this. I am working on Ubuntu 12.10 and Python 2.7.3.
13 Answers
...
chart.js load totally new data
...eight
var x = canvas.width/2;
var y = canvas.height/2;
ctx.font = '10pt Verdana';
ctx.textAlign = 'center';
ctx.fillText('This text is centered on the canvas', x, y);
};
share
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improve ...
Homebrew install specific version of formula?
...ormula in homebrew? For example, postgresql-8.4.4 instead of the latest 9.0.
27 Answers
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Using try vs if in python
... faster if exceptions really are exceptional. If result is None more than 50 % of the time, then using if is probably better.
To support this with a few measurements:
>>> import timeit
>>> timeit.timeit(setup="a=1;b=1", stmt="a/b") # no error checking
0.06379691968322732
>>...
Are lists thread-safe?
...to concurrently access, the lists's data is not protected. For example:
L[0] += 1
is not guaranteed to actually increase L[0] by one if another thread does the same thing, because += is not an atomic operation. (Very, very few operations in Python are actually atomic, because most of them can cau...
Selecting multiple columns in a pandas dataframe
...s of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of the ending index.
Additionally, you should familiarize yourself with the idea of a view into a Pandas object vs. a copy of that object. The first of the above methods w...
How to get the last element of a slice?
...
307
For just reading the last element of a slice:
sl[len(sl)-1]
For removing it:
sl = sl[:len(s...
How to get last items of a list in Python?
...the python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
s...
In Jinja2, how do you test if a variable is undefined?
... |
edited Jul 29 '14 at 0:16
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How can I multiply and divide using only bit shifting and adding?
...want to decompose one of the numbers by powers of two, like so:
21 * 5 = 10101_2 * 101_2 (Initial step)
= 10101_2 * (1 * 2^2 + 0 * 2^1 + 1 * 2^0)
= 10101_2 * 2^2 + 10101_2 * 2^0
= 10101_2 << 2 + 10101_2 << 0 (Decomposed)
= 10101_2 * 4 + 10101...