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How do I replace NA values with zeros in an R dataframe?
...am running these tests on fully numeric dataframes.
Hardware Used
3.9 GHz CPU with 24 GB RAM
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How to append rows to an R data frame
...t(r)
For 1E5 rows (measurements done on Intel(R) Core(TM) i7-4710HQ CPU @ 2.50GHz):
nr function time
4 data.frame 228.251
3 sqlite 133.716
2 data.table 3.059
1 rbindlist 169.998
0 placebo 0.202
It looks like the SQLite-based sulution, although r...
Why does changing 0.1f to 0 slow down performance by 10x?
... sets FTZ (flush to zero) and DAZ (denormal are zero) in the MXCSR, so the CPU never has to take a slow microcode assist for denormals.
– Peter Cordes
Jan 16 '19 at 10:23
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What are the differences between a multidimensional array and an array of arrays in C#?
...nal but my guess is that it has to do with some optimalization made on the CPU
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In which order should floats be added to get the most precise result?
...bly avoid using -ffast-math but that in many applications where you may be CPU-bound but don't care about precise numerical computations, (game programming for instance), -ffast-math is reasonable to use. Thus, I'd like to ammend my strongly worded "banned" comment.
– Chris A....
Proper practice for subclassing UIView?
...s. Personally, I avoid multi-pass layouts when possible because they burn CPU cycles and make everything a headache. Additionally, I put constraint code in the initializers themselves as I rarely invalidate them.
import UIKit
class MyView: UIView {
//------------------------------------------...
How does LMAX's disruptor pattern work?
...nd because readers read entries sequentially, this is important to utilize CPU caches.
And lots of efforts to avoid lock, CAS, even memory barrier (e.g. use a non-volatile sequence variable if there's only one writer)
For developers of readers: Different annotating readers should write to differen...
Is R's apply family more than syntactic sugar?
... It does vary with OS and R version... and in an absolute sense CPU. I just ran with 2.15.2 on Mac and got sapply 50% slower than for and lapply twice as fast.
– John
Jan 13 '13 at 0:08
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Java 8: performance of Streams vs Collections
... I think your test is fair, you just need a machine has more cpu cores.
– Mellon
Nov 19 '15 at 19:34
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Why should I not include cpp files and instead use a header?
...ng with a tiny tiny little program, and a nice and relatively unencumbered CPU to compile it for you. You won't always be so lucky.
If you ever delve into the realms of serious computer programming, you'll be seeing projects with line counts that can reach millions, rather than dozens. That's a l...