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Measure time in Linum>x m> - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
...on the wall (or desktop).
Here's what I've found so far for clocks in Linum>x m> and OS m>X m>:
time() returns the wall-clock time from the OS, with precision in seconds.
clock() seems to return the sum of user and system time. It is present in C89 and later. At one time this was supposed to be the CPU tim...
How to get one value at a time from a generator function in Python?
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Yes, or nem>x m>t(gen) in 2.6+.
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Why should eval be avoided in Bash, and what should I use instead?
...n meets the eye. We'll start with the obvious: eval has the potential to em>x m>ecute "dirty" data. Dirty data is any data that has not been rewritten as safe-for-use-in-situation-m>X m>YZ; in our case, it's any string that has not been formatted so as to be safe for evaluation.
Sanitizing data appears eas...
Releasing memory in Python
I have a few related questions regarding memory usage in the following em>x m>ample.
4 Answers
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CSS hide scroll bar if not needed
...s will be displayed and I want to hide the scroll bar if content does not em>x m>ceed the current width.
5 Answers
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Em>x m>tracting the last n characters from a string in R
...'s straight-forward to make a function to do this using substr and nchar:
m>x m> <- "some tem>x m>t in a string"
substrRight <- function(m>x m>, n){
substr(m>x m>, nchar(m>x m>)-n+1, nchar(m>x m>))
}
substrRight(m>x m>, 6)
[1] "string"
substrRight(m>x m>, 8)
[1] "a string"
This is vectorised, as @mdsumner points out. Cons...
Should I use a data.frame or a matrim>x m>?
When should one use a data.frame , and when is it better to use a matrim>x m> ?
6 Answers
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How does the const constructor actually work?
...st constructor creates a "canonicalized" instance.
That is, all constant em>x m>pressions begin canonicalized, and later these "canonicalized" symbols are used to recognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible representation in...
Convert Year/Month/Day to Day of Year in Python
... answered Mar 8 '09 at 9:27
Dzinm>X m>Dzinm>X m>
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How to insert a newline in front of a pattern?
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This works in bash and zsh, tested on Linum>x m> and OS m>X m>:
sed 's/regem>x m>p/\'$'\n/g'
In general, for $ followed by a string literal in single quotes bash performs C-style backslash substitution, e.g. $'\t' is translated to a literal tab. Plus, sed wants your newline lite...