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Replacing NAs with latest non-NA value
...,'a',NA,NA,NA,NA,NA,NA,NA,NA,'b','c','d',NA,NA,NA,NA,NA,'e')
xx = rep(x, 1000000)
system.time({ yzoo = na.locf(xx,na.rm=F)})
## user system elapsed
## 2.754 0.667 3.406
system.time({ yrep = repeat.before(xx)})
## user system elapsed
## 0.597 0.199 0.793
Edit
As this ...
Changing specific text's color using NSMutableAttributedString in Swift
...ange: range)
textField = UITextField.init(frame: CGRect(x:10, y:20, width:100, height: 100))
textField.attributedText = mutableAttributedString
SWIFT 4.2
let range = (mainString as NSString).range(of: stringToColor)
let mutableAttributedString = NSMutableAttributedString.init(string: mainStr...
What is the best way to get all the divisors of a number?
...
wow it took 0.01 for calculating all divisors of 100000000 against the 39s that took the dumb way (stopping at n/2) very cool, thank you!
– Andrea Ambu
Oct 5 '08 at 10:20
...
Export database schema into SQL file
...DENTITY(1,1)
,DatabaseName VARCHAR(100)
,TableOwner VARCHAR(100)
,TableName VARCHAR(100)
,FieldName VARCHAR(100)
...
in_array() and multidimensional array
...$userdb = Array
(
(0) => Array
(
('uid') => '100',
('name') => 'Sandra Shush',
('url') => 'urlof100'
),
(1) => Array
(
('uid') => '5465',
('name') => 'Stefanie Mcmohn',
('url...
Which is the preferred way to concatenate a string in Python?
...(b):
0.010656118392944336
The end string, therefore, ends up being about 100MB long. That was pretty slow, appending to a list was much faster. That that timing doesn't include the final a.join(). So how long would that take?
a.join(a):
0.43739795684814453
Oups. Turns out even in this case, ap...
CSS Display an Image Resized and Cropped
...
width: 400px;
height: 300px;
margin: -75px 0 0 -100px;
}
<div class="crop">
<img src="https://i.stack.imgur.com/wPh0S.jpg" alt="Donald Duck">
</div>
You can use negative margin to move the image around within the <div/>...
Find unique rows in numpy.array
..., or even better, than the lexsort method:
a = np.random.randint(2, size=(10000, 6))
%timeit np.unique(a.view(np.dtype((np.void, a.dtype.itemsize*a.shape[1])))).view(a.dtype).reshape(-1, a.shape[1])
100 loops, best of 3: 3.17 ms per loop
%timeit ind = np.lexsort(a.T); a[np.concatenate(([True],np....
How do I format a number in Java?
...alue();
System.out.println(r); // r is 5.12
f = (float) (Math.round(n*100.0f)/100.0f);
DecimalFormat df2 = new DecimalFormat( "#,###,###,##0.00" );
double dd = 100.2397;
double dd2dec = new Double(df2.format(dd)).doubleValue();
// The value of dd2dec will be 100.24
The DecimalFormat() se...
jQuery DataTables: control table width
...f a table using the jQuery DataTables plugin. The table is supposed to be 100% of the container width, but ends up being an arbitrary width, rather less than the container width.
...