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Are there any O(1/n) algorithms?
...he following one:
def get_faster(list):
how_long = (1 / len(list)) * 100000
sleep(how_long)
Clearly, this function spends less time as the input size grows … at least until some limit, enforced by the hardware (precision of the numbers, minimum of time that sleep can wait, time to proce...
Generate a random double in a range
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edited Sep 27 '15 at 18:03
answered Sep 9 '10 at 21:17
mo...
How to use Active Support core extensions
I have Active Support 3.0.3 installed and Rails 3.0.3 with Ruby 1.8.7.
5 Answers
5
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How can I shrink the drawable on a button?
...rawable = getResources().getDrawable(R.drawable.s_vit);
drawable.setBounds(0, 0, (int)(drawable.getIntrinsicWidth()*0.5),
(int)(drawable.getIntrinsicHeight()*0.5));
ScaleDrawable sd = new ScaleDrawable(drawable, 0, scaleWidth, scaleHeight);
Button btn = findViewbyId(R.id.yo...
What is the best way to convert seconds into (Hour:Minutes:Seconds:Milliseconds) time?
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For .Net <= 4.0 Use the TimeSpan class.
TimeSpan t = TimeSpan.FromSeconds( secs );
string answer = string.Format("{0:D2}h:{1:D2}m:{2:D2}s:{3:D3}ms",
t.Hours,
t.Minutes,
t.Seconds,
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Which method performs better: .Any() vs .Count() > 0?
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edited Nov 20 '08 at 12:51
answered Nov 20 '08 at 12:37
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Is it safe to check floating point values for equality to 0?
...ality between double or decimal type values normally, but I'm wondering if 0 is a special case.
9 Answers
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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