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How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
CSS triangle custom border color
...sure how to go about doing this. I would like to steer clear of javascript and css3 simply because of compatibility. I am trying to have the triangle have a white background with a 1px border (around the angled sides of the triangle) with color #CAD5E0. Is this possible? Here's what I have so far:
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Linear Layout and weight in Android
I always read about this funny weight value in the Android documentations.
Now I want to try it for the first time but it isn't working at all.
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C# DateTime to “YYYYMMDDHHMMSS” format
...M = months, h = 12 hour, H = 24 hour. I suspect someone started with time and said hms = hours mins seconds, then H became 24 hour and then they got to date and ran out of unique letters so went with case. Just one of those things.
– Douglas Anderson
May 23 '...
What do the numbers in a version typically represent (i.e. v1.9.0.1)?
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I'm trying to understand this system. So here is a question: What if a new release has a feature and a bug fix, what should I increment?
– iTurki
Jul 16 '13 at 19:36
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Total memory used by Python process?
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psutil is cross platform and can return the same values as the ps command line tool: pythonhosted.org/psutil/#psutil.Process.memory_info
– amos
Jul 3 '14 at 21:38
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What's the best way to check if a String represents an integer in Java?
...nge looking. I would have used (c < '0' || c > '9')... are the <= and >= operators faster in Java?
– Anonymous
Oct 26 '08 at 1:43
3
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CSS to set A4 paper size
I need simulate an A4 paper in web and allow to print this page as it is show on browser (Chrome, specifically). I set the element size to 21cm x 29.7cm, but when I send to print (or print preview) it clip my page.
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How to convert index of a pandas dataframe into a column?
...26 C 2 0.0139
2016-02-27 A 2 0.5577
2016-02-28 C 6 0.0303
and you want to convert the 1st (tick) and 3rd (obs) levels in the index into columns, you would do:
>>> df.reset_index(level=['tick', 'obs'])
tick obs val
tag
C 2016-02-26 ...
How can I create a two dimensional array in JavaScript?
I have been reading online and some places say it isn't possible, some say it is and then give an example and others refute the example, etc.
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