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What do the terms “CPU bound” and “I/O bound” mean?
...:
#define SIZE 1000000000
unsigned int is[SIZE];
unsigned int sum = 0;
size_t i = 0;
for (i = 0; i < SIZE; i++)
/* Each one of those requires a RAM access! */
sum += is[i]
Parallelizing that by splitting the array equally for each of your cores is of limited usefulness on common modern d...
How to detect if app is being built for device or simulator in Swift
...ect iOS on a desktop architecture like follows
#if (arch(i386) || arch(x86_64)) && os(iOS)
...
#endif
After Swift 4.1 version
Latest use, now directly for all in one condition for all types of simulators need to apply only one condition -
#if targetEnvironment(simulator)
// ...
What is the easiest way to remove the first character from a string?
... fastest and most readable way of doing things:
require 'benchmark'
N = 1_000_000
puts RUBY_VERSION
STR = "[12,23,987,43"
Benchmark.bm(7) do |b|
b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } }
b.report('sub') { N.times { "[12,23,987,43".sub(/^\[+/, "") } }
b.report('gsub') { N.ti...
How can I sanitize user input with PHP?
..., you must escape the string with MySQL's function for this purpose (mysqli_real_escape_string). (Or, in case of databases, using prepared statements are a better approach, when possible.)
Another example is HTML: If you embed strings within HTML markup, you must escape it with htmlspecialchars. Th...
How to create a density plot in matplotlib?
...
Sven has shown how to use the class gaussian_kde from Scipy, but you will notice that it doesn't look quite like what you generated with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the...
How can I change UIButton title color?
...
With Swift 5, UIButton has a setTitleColor(_:for:) method. setTitleColor(_:for:) has the following declaration:
Sets the color of the title to use for the specified state.
func setTitleColor(_ color: UIColor?, for state: UIControlState)
The following Playgro...
Image Greyscale with CSS & re-color on mouse-over?
...kground: url(http://4.bp.blogspot.com/-IzPWLqY4gJ0/T01CPzNb1KI/AAAAAAAACgA/_8uyj68QhFE/s400/a2cf7051-5952-4b39-aca3-4481976cb242.jpg);
}
svg image {
transition: all .6s ease;
}
svg image:hover {
opacity: 0;
}
<p>Firefox, Chrome, Safari, IE6-9</p>
<img class="grayscale...
C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
Rails raw SQL example
...
You can do this:
sql = "Select * from ... your sql query here"
records_array = ActiveRecord::Base.connection.execute(sql)
records_array would then be the result of your sql query in an array which you can iterate through.
...
Getting a better understanding of callback functions in JavaScript
...epending how you call the function
alert(this);
};
callback(argument_1, argument_2);
callback.call(some_object, argument_1, argument_2);
callback.apply(some_object, [argument_1, argument_2]);
The method you choose depends whether:
You have the arguments stored in an Array or as distinct v...