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Java; String replace (using regular expressions)?
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ah... but you missed collapsing the "5 * x" to "5x"
– James Curran
Mar 10 '09 at 20:53
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Simple way to calculate median with MySQL
...fully not too slow) way to calculate the median with MySQL? I've used AVG(x) for finding the mean, but I'm having a hard time finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but surely there must be some sim...
git pull while not in a git directory
Let's say I have a directory, /X/Y , which is a git repository. Is it possible to somehow call a command like git pull from inside /X , but targeting the /X/Y directory?
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Why can't I declare static methods in an interface?
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Good answer, though "approximately equivalent" ROFLMAO xD I would have put it more like "somewhat resembles".
– Timo
May 18 '15 at 12:51
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How do JavaScript closures work?
How would you explain JavaScript closures to someone with a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?
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Comparing two dictionaries and checking how many (key, value) pairs are equal
... should have said that :)
Maybe something like this:
shared_items = {k: x[k] for k in x if k in y and x[k] == y[k]}
print len(shared_items)
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filter for complete cases in data.frame using dplyr (case-wise deletion)
...on one variable's missingness, use a conditional:
df %>% filter(!is.na(x1))
or
df %>% drop_na(x1)
Other answers indicate that of the solutions above na.omit is much slower but that has to be balanced against the fact that it returns row indices of the omitted rows in the na.action attrib...
Syntax behind sorted(key=lambda: …)
I don't quite understand the syntax behind the sorted() argument:
9 Answers
9
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Split (explode) pandas dataframe string entry to separate rows
I have a pandas dataframe in which one column of text strings contains comma-separated values. I want to split each CSV field and create a new row per entry (assume that CSV are clean and need only be split on ','). For example, a should become b :
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What is normalized UTF-8 all about?
...same result as comparing them under NFD.
NFD
NFD has the characters fully expanded out. This is the faster normalization form to calculate, but the results in more code points (i.e. uses more space).
If you just want to compare two strings that are not already normalized, this is the preferred norma...