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How to append rows to an R data frame
...sive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5
# f3(1000) ...
How to specify Composer install path?
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140
It seems that you can define the vendor dir to be something else (plugins in your case):
{
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How do I get time of a Python program's execution?
...s that your program takes at least a tenth of second to run.
Prints:
--- 0.764891862869 seconds ---
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Add unique constraint to combination of two columns
...g an exception (exceptions are expensive).
http://www.sqlperformance.com/2012/08/t-sql-queries/error-handling
http://www.mssqltips.com/sqlservertip/2632/checking-for-potential-constraint-violations-before-entering-sql-server-try-and-catch-logic/
If you want to prevent exceptions from bubbling up ...
Bash Script: count unique lines in file
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306
You can use the uniq command to get counts of sorted repeated lines:
sort ips.txt | uniq -c
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Cluster analysis in R: determine the optimal number of clusters
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1024
If your question is how can I determine how many clusters are appropriate for a kmeans analysi...
Ruby: Merging variables in to a string
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answered Feb 16 '09 at 21:42
Mike WoodhouseMike Woodhouse
47.6k1212 gold badges8585 silver badges123123 bronze badges
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How to do version numbers? [closed]
...e "unstable watchout" on there. So how would you go about versioning? Is 1.0 stable? Should the build date be in the version number? Tell me what you guys think!
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Overlaying histograms with ggplot2 in R
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Your current code:
ggplot(histogram, aes(f0, fill = utt)) + geom_histogram(alpha = 0.2)
is telling ggplot to construct one histogram using all the values in f0 and then color the bars of this single histogram according to the variable utt.
What you want instead is...
Sass negative variable value?
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Try it like this
margin: 0 (-$pad) 20px (-$pad);
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