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Summarizing multiple columns with dplyr? [duplicate]
...0000 2.750000
3 3 3.000000 4.00 4.333333 3.666667
but it is slower, at least in this case:
> microbenchmark(ddply(df, .(grp), colwise(mean)),
df %>% group_by(grp) %>% summarise_each(funs(mean)))
Unit: milliseconds
expr ...
__getattr__ on a module
...ce-substitution behavior; and (2) means that (1) isn't even possible... at least not directly.
Fortunately, sys.modules is not picky about what goes there so a wrapper will work, but only for module access (i.e. import somemodule; somemodule.salutation('world'); for same-module access you pretty mu...
Subprocess changing directory
...o. As no process can change another process's working directory (again, at least on a UNIX-like OS, but as well on Windows), this call will have the subshell change its dir and exit immediately.
What you want can be achieved with os.chdir() or with the subprocess named parameter cwd which changes t...
C++ : why bool is 8 bits long?
...o have char the smallest hardware addressable unit. This has been used at least in some C compilers for old word addressable architectures.
– AProgrammer
Jan 14 '10 at 15:01
...
How to validate IP address in Python? [duplicate]
... @quux: no. It's a long discussion, and people don't like the fact that at least on Linux and Windows shortened addresses are considered acceptable. For example, socket.inet_aton('127.1') evaluates to '\x7f\x00\x00\x01' (i.e. exactly like '127.0.0.1' does). I've had this tiresome and lengthy discuss...
Difference between InvariantCulture and Ordinal string comparison
... For those that don't know ß it should be noted that ß at least in german equals to a double s, Source: en.wikipedia.org/wiki/%C3%9F
– Peter
Mar 2 '16 at 7:46
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How do I catch a PHP fatal (`E_ERROR`) error?
...ude "filename.php" instead in the try block, then Throwable catch block at least works for ParseError.
– Niloct
Nov 1 '18 at 18:09
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Trimming a huge (3.5 GB) csv file to read into R
... yourself wanting to read many gigs of delimited data into R you should at least research the sqldf package which allows you to import directly into sqldf from R and then operate on the data from within R. I've found sqldf to be one of the fastest ways to import gigs of data into R, as mentioned in ...
How to disable GCC warnings for a few lines of code
...dn.microsoft.com/de-DE/library/d9x1s805.aspx for more details
You need at least version 4.02 to use these kind of pragmas for gcc, not sure about msvc and clang about the versions.
It looks like the push pop pragma handling for gcc is a little bit broken. If you enable the warning again, you still...
What are advantages of Artificial Neural Networks over Support Vector Machines? [closed]
...lus bias parameters, and those make up your model. By contrast, an SVM (at least a kernelized one) consists of a set of support vectors, selected from the training set, with a weight for each. In the worst case, the number of support vectors is exactly the number of training samples (though that mai...