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Which UUID version to use?
...ique values. It would belong in a RFC about generating randomness. For a set of random numbers:
chance_of_collision = 1 - (set_size! / (set_size - tries)!) / (set_size ^ tries)
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Remove duplicated rows
...ortant feature of these methods is a huge performance gain for larger data sets
library(microbenchmark)
library(data.table)
set.seed(123)
DF <- as.data.frame(matrix(sample(1e8, 1e5, replace = TRUE), ncol = 10))
DT <- copy(DF)
setDT(DT)
microbenchmark(unique(DF), unique(DT))
# Unit: microseco...
How do cache lines work?
...dirty and needs to wrote back in ram etc).
Another aspect is that we have set-associative cache. Not every cache cell is able to store a certain address but only a subset of those. This makes the necessary stored address bits even smaller, allows parallel access of the cache (each subset can be acc...
horizontal line and right way to code it in html, css
... question "Which is the most practical?"
– Brian Tompsett - 汤莱恩
Jan 20 '19 at 14:33
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How to include() all PHP files from a directory?
...
You can use set_include_path:
set_include_path('classes/');
http://php.net/manual/en/function.set-include-path.php
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Centering floating divs within another div
...e able to accomplish what you want as long as you're floating /unless/ you set a fixed width on the container of the floats.
– Ken Browning
Aug 12 '09 at 23:44
1
...
Bootstrap 3 Flush footer to bottom. not fixed
...: 60px;
}
.footer {
position: absolute;
bottom: 0;
width: 100%;
/* Set the fixed height of the footer here */
height: 60px;
background-color: #f5f5f5;
}
for this HTML
<html>
...
<body>
<!-- Begin page content -->
<div class="container">
...
How to delete all Annotations on a MKMapView
...mapView.annotations];
And as long as you have mapView.showsUserLocation set to YES, you will still have user location on the map. Settings this property to YES basically asks the map view to start updating and fetching user location, to to show it on the map. From the MKMapView.h comments:
// Se...
How to set the prototype of a JavaScript object that has already been instantiated?
...it isn't required to be implemented but if it is, it must follow the given set of rules. This is currently unresolved but at least it will be officially part of JavaScript's specification.
This question is a lot more complicated than it seems on the surface, and beyond most peoples' pay grade in re...
How do I turn a String into a InputStreamReader in java?
... trick:
InputStream is = new ByteArrayInputStream( myString.getBytes( charset ) );
Then convert to reader:
InputStreamReader reader = new InputStreamReader(is);
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