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Swift performSelector:withObject:afterDelay: is unavailable [duplicate]
... answered Jun 11 '14 at 19:11
brandonscriptbrandonscript
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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
I would like to write a single SQL command to drop multiple columns from a single table in one ALTER TABLE statement.
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Get a pixel from HTML Canvas?
....getContext('2d');
// Get the CanvasPixelArray from the given coordinates and dimensions.
var imgd = context.getImageData(x, y, width, height);
var pix = imgd.data;
// Loop over each pixel and invert the color.
for (var i = 0, n = pix.length; i < n; i += 4) {
pix[i ] = 255 - pix[i ]; // r...
Counting the number of elements with the values of x in a vector
... x creates a logical vector which is TRUE at every location that x occurs, and when suming, the logical vector is coerced to numeric which converts TRUE to 1 and FALSE to 0.
However, note that for floating point numbers it's better to use something like: sum(abs(numbers - x) < 1e-6).
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Adding values to a C# array
Probably a really simple one this - I'm starting out with C# and need to add values to an array, for example:
23 Answers
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Converting Mercurial folder to a Git repository
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If you are on Windows machine use the Git bash and run hg-fast-export.sh
– Augustas
Dec 7 '17 at 13:45
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Can Python test the membership of multiple values in a list?
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This does what you want, and will work in nearly all cases:
>>> all(x in ['b', 'a', 'foo', 'bar'] for x in ['a', 'b'])
True
The expression 'a','b' in ['b', 'a', 'foo', 'bar'] doesn't work as expected because Python interprets it as a tupl...
Get elements by attribute when querySelectorAll is not available without using libraries?
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You could write a function that runs getElementsByTagName('*'), and returns only those elements with a "data-foo" attribute:
function getAllElementsWithAttribute(attribute)
{
var matchingElements = [];
var allElements = document.getElementsByTagName('*');
for (var i = 0, n = allEle...
Map over object preserving keys
...h Underscore
Underscore provides a function _.mapObject to map the values and preserve the keys.
_.mapObject({ one: 1, two: 2, three: 3 }, function (v) { return v * 3; });
// => { one: 3, two: 6, three: 9 }
DEMO
With Lodash
Lodash provides a function _.mapValues to map the values and pre...
Creating and playing a sound in swift
So what I want to do is create and play a sound in swift that will play when I press a button, I know how to do it in Objective-C, but does anyone know how to in Swift?
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