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What does .SD stand for in data.table in R
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206
.SD stands for something like "Subset of Data.table". There's no significance to the initial "....
How to select a single field for all documents in a MongoDB collection?
In my MongoDB, I have a student collection with 10 records having fields name and roll . One record of this collection is:
...
How to capture UIView to UIImage without loss of quality on retina display
... UIGraphicsBeginImageContextWithOptions (as documented on this page). Pass 0.0 for scale (the third argument) and you'll get a context with a scale factor equal to that of the screen.
UIGraphicsBeginImageContext uses a fixed scale factor of 1.0, so you're actually getting exactly the same image on ...
Regex exactly n OR m times
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answered Dec 14 '12 at 8:10
Mark ByersMark Byers
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通信连接组件 · App Inventor 2 中文网
...的「版本号」。
本机版本名
当前应用的版本名，如 1.0，对应屏幕属性里的「版本名」。
正在下载
是否正在下载安装包。
通知栏显示进度
下载时在通知栏显示进度条，默认为真。
使用内置对话框
默认为真：发现...
chart.js load totally new data
...eight
var x = canvas.width/2;
var y = canvas.height/2;
ctx.font = '10pt Verdana';
ctx.textAlign = 'center';
ctx.fillText('This text is centered on the canvas', x, y);
};
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Increase number of axis ticks
...continuous. For example:
library(ggplot2)
dat <- data.frame(x = rnorm(100), y = rnorm(100))
ggplot(dat, aes(x,y)) +
geom_point()
Gives you this:
And overriding the scales can give you something like this:
ggplot(dat, aes(x,y)) +
geom_point() +
scale_x_continuous(breaks = round(seq(m...
Mongoose query where value is not null
...May 13 '13 at 22:11
numbers1311407numbers1311407
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How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
...NSString = str as NSString
myNSString.substringWithRange(NSRange(location: 0, length: 3))
Note: as JanX2 mentioned, this second method is not safe with unicode strings.
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Locate the nginx.conf file my nginx is actually using
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$ nginx -V
nginx version: nginx/1.11.1
built by gcc 4.9.2 (Debian 4.9.2-10)
built with OpenSSL 1.0.1k 8 Jan 2015
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf ...
If you want, y...