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Convert a list of data frames into one data frame
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answered Feb 27 '18 at 20:05
joekliegjoeklieg
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Drawing a dot on HTML5 canvas [duplicate]
...d it. Just draw a rectangle with a width and height of one:
ctx.fillRect(10,10,1,1); // fill in the pixel at (10,10)
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Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
How do I find the time difference between two datetime objects in python?
...; difference = later_time - first_time
>>> seconds_in_day = 24 * 60 * 60
datetime.timedelta(0, 8, 562000)
>>> divmod(difference.days * seconds_in_day + difference.seconds, 60)
(0, 8) # 0 minutes, 8 seconds
Subtracting the later time from the first time difference = later_tim...
Aligning text and image on UIButton with imageEdgeInsets and titleEdgeInsets
... already does so we simply need to adjust the spacing.
CGFloat spacing = 10; // the amount of spacing to appear between image and title
tabBtn.imageEdgeInsets = UIEdgeInsetsMake(0, 0, 0, spacing);
tabBtn.titleEdgeInsets = UIEdgeInsetsMake(0, spacing, 0, 0);
I also turned this into a category for ...
Python Infinity - Any caveats?
...-a-number (NaN) values from simple arithmetic involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**...
Principal component analysis in Python
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edited Sep 3 '10 at 11:40
nikow
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answe...
What is the difference between CMD and ENTRYPOINT in a Dockerfile?
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edited May 9 '18 at 20:46
Software Engineer
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Getting key with maximum value in dictionary?
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You can use operator.itemgetter for that:
import operator
stats = {'a':1000, 'b':3000, 'c': 100}
max(stats.iteritems(), key=operator.itemgetter(1))[0]
And instead of building a new list in memory use stats.iteritems(). The key parameter to the max() function is a function that computes a key th...
Bin size in Matplotlib (Histogram)
... boundaries. They can be unequally distributed, too:
plt.hist(data, bins=[0, 10, 20, 30, 40, 50, 100])
If you just want them equally distributed, you can simply use range:
plt.hist(data, bins=range(min(data), max(data) + binwidth, binwidth))
Added to original answer
The above line works for...