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Convert column classes in data.table
...rter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(....
How do I use CMake?
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32
CMake takes a CMakeList file, and outputs it to a platform-specific build format, e.g. a Makefi...
How is pattern matching in Scala implemented at the bytecode level?
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3 Answers
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Make Div overlay ENTIRE page (not just viewport)?
...pression that the entire body is darkened.
Example: http://jsbin.com/okabo3/edit
div.fadeMe {
opacity: 0.5;
background: #000;
width: 100%;
height: 100%;
z-index: 10;
top: 0;
left: 0;
position: fixed;
}
<body>
<div class="fadeMe">...
Disabling Strict Standards in PHP 5.4
...rently running a site on php 5.4, prior to this I was running my site on 5.3.8. Unfortunately, php 5.4 combines E_ALL and E_STRICT , which means that my previous setting for error_reporting does not work now. My previous value was E_ALL & ~E_NOTICE & ~E_STRICT Should I just enable val...
POSTing a @OneToMany sub-resource association in Spring Data REST
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uniruddh
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answered Oct 17 '14 at 14:09
Chetan KokilChetan Ko...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
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URL query parameters to dict python
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193
Use the urllib.parse library:
>>> from urllib import parse
>>> url = "http://...
Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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