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Why doesn't c++ have &&= or ||= for booleans?
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Passing multiple error classes to ruby's rescue clause in a DRY fashion
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Bash tool to get nth line from a file
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832
head and pipe with tail will be slow for a huge file. I would suggest sed like this:
sed 'NUMq...
Cluster analysis in R: determine the optimal number of clusters
...inity propagation (AP) clustering, see http://dx.doi.org/10.1126/science.1136800
library(apcluster)
d.apclus <- apcluster(negDistMat(r=2), d)
cat("affinity propogation optimal number of clusters:", length(d.apclus@clusters), "\n")
# 4
heatmap(d.apclus)
plot(d.apclus, d)
Six. Gap Statistic f...
Split comma-separated strings in a column into separate rows
...th more than about 5000 rows, Jaap's data.table method 2 and the variant DT3 are the fastest, magnitudes faster than the slowest methods.
Remarkably, the timings of the two tidyverse methods and the splistackshape solution are so similar that it's difficult to distiguish the curves in the chart. T...
What are best practices for validating email addresses on iOS 2.0
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Is it better to use std::memcpy() or std::copy() in terms to performance?
...ion. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the memcpy version and the std::copy ver...
How to trace the path in a Breadth-First Search?
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# graph is in adjacent list representation
graph = {
'1': ['2', '3', '4'],
'2': ['5', '6'],
'5': ['9', '10'],
'4': ['7', '8'],
'7': ['11', '12']
}
def bfs(graph, start, end):
# maintain a queue of paths
queue = []
# push the first path i...