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How is the java memory pool divided?
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332
Heap memory
The heap memory is the runtime data area from which the Java VM allocates memory fo...
Is log(n!) = Θ(n·log(n))?
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Remember that
log(n!) = log(1) + log(2) + ... + log(n-1) + log(n)
You can get the upper bound by
log(1) + log(2) + ... + log(n) <= log(n) + log(n) + ... + log(n)
= n*log(n)
And you can get the lower bound by doing a simil...
Is it possible to do a sparse checkout without checking out the whole repository first?
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32
In 2020 there is a simpler way to deal with sparse-checkout without having to worry about .git f...
Add new row to dataframe, at specific row-index, not appended?
...ds the (often slow) rbind call:
existingDF <- as.data.frame(matrix(seq(20),nrow=5,ncol=4))
r <- 3
newrow <- seq(4)
insertRow <- function(existingDF, newrow, r) {
existingDF[seq(r+1,nrow(existingDF)+1),] <- existingDF[seq(r,nrow(existingDF)),]
existingDF[r,] <- newrow
existin...
Reset the database (purge all), then seed a database
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280
I use rake db:reset which drops and then recreates the database and includes your seeds.rb fil...
Fastest way to extract frames using ffmpeg?
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edited Jun 9 '12 at 18:28
answered Jun 9 '12 at 15:53
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How to correctly require a specific commit in Composer so that it would be available for dependent p
... "foo/foo-lib": "dev-master",
"knplabs/gaufrette": "dev-master#2633721877cae79ad461f3ca06f3f77fb4fce02e"
}
}
From the documentation:
If one of your dependencies has a dependency on an unstable package
you need to explicitly require it as well, along with its sufficient
stab...
WPF ToolBar: how to remove grip and overflow
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answered Jun 26 '09 at 20:57
rmoorermoore
14.2k44 gold badges5656 silver badges5959 bronze badges
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What's the fastest way to merge/join data.frames in R?
...s for duplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c
1 1 1 a
2 2 1 b
3 3 2 c
4 3 2 d
5 4 2 e
DF1$c = DF2$c[match(DF1$b, DF2$b)]
DF1$c
[1] a b c e
Levels: a b c d e
>...