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how to rotate a bitmap 90 degrees
There is a statement in android canvas.drawBitmap(visiblePage, 0, 0, paint);
10 Answers
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Can dplyr package be used for conditional mutating?
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220
Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
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How can I scale an image in a CSS sprite
... not all http://caniuse.com/#search=background-size)
background-size : 150% 150%;
Or
You can use a combo of zoom for webkit/ie and transform:scale for Firefox(-moz-) and Opera(-o-) for cross-browser desktop & mobile
[class^="icon-"]{
display: inline-block;
background: url('../img/...
How do I use vim registers?
... D. Ben Knoble
3,47211 gold badge1717 silver badges3030 bronze badges
answered Sep 30 '09 at 13:12
FModa3FModa3
12.7k11 gold badge...
Why does one hot encoding improve machine learning performance?
...h" and "US". Assume, without loss of generality, that these are encoded as 0, 1 and 2. You then have a weight w for this feature in a linear classifier, which will make some kind of decision based on the constraint w×x + b > 0, or equivalently w×x < b.
The problem now is that the weight w c...
How to wait in a batch script? [duplicate]
I am trying to write a batch script and trying to wait 10 seconds between 2 function calls. The command:
6 Answers
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
Creating a comma separated list from IList or IEnumerable
...ng"};
string joined = string.Join(",", strings);
Detail & Pre .Net 4.0 Solutions
IEnumerable<string> can be converted into a string array very easily with LINQ (.NET 3.5):
IEnumerable<string> strings = ...;
string[] array = strings.ToArray();
It's easy enough to write the equiv...
Check if UIColor is dark or bright?
...o use is ((Red value * 299) + (Green value * 587) + (Blue value * 114)) / 1000.
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Validate decimal numbers in JavaScript - IsNumeric()
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2908
@Joel's answer is pretty close, but it will fail in the following cases:
// Whitespace strings...