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Apply formula to the entire column
I'm trying to recode all the zip code from Column A into Column B with the formula:
10 Answers
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Sample random rows in dataframe
I am struggling to find the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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efficient way to implement paging
...irect paging in the SQL engine.
Giving you an example, I have a db table called mtcity and I wrote the following query (work as well with linq to entities):
using (DataClasses1DataContext c = new DataClasses1DataContext())
{
var query = (from MtCity2 c1 in c.MtCity2s
select c1)...
Understanding spring @Configuration class
Following the question Understanding Spring @Autowired usage I wanted to create a complete knowledge base for the other option of spring wiring, the @Configuration class.
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What is AF_INET, and why do I need it?
I'm getting started on socket programming, and I keep seeing this AF_INET .
5 Answers
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Valid to use (anchor tag) without href attribute?
I've been using Twitter Bootstrap to build a site, and a lot of its functionality depends on wrapping things in <a> , even if they're just going to execute Javascript. I've had problems with the href="#" tactic that Bootstrap's documentation recommends, so I was trying to find a different s...
Persistence unit as RESOURCE_LOCAL or JTA?
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Error message “Forbidden You don't have permission to access / on this server” [closed]
...ronments,
in addition I would like to explain some issues that you might fall into while setting up your environment.
If you are looking for a quick solution and SECURITY IS NOT A MATTER, i.e development env, skip and read the original answer instead
Many scenarios can lead to 403 Forbidden:
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Can I change the root EBS device of my amazon EC2 instance?
I have an EBS backed Amazon EC2 instance. I would like to change the root device on this instance. Can you please advise the best way to go about this?
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Linux, Why can't I write even though I have group permissions?
I want to create a file in a directory owned by the staff group which I am a member of. Why can I not do this?
6 Answers
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