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Explicitly calling return in a function or not
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Question was: Why is not (explicitly) calling return faster or better, and thus preferable?
There is no statement in R documentation making such an assumption.
The main page ?'function' says:
function( arglist ) expr
return(value)
Is it faster without calling return?
Both function() and re...
Extract month and year from a zoo::yearmon object
... "%m"))
[1] 3
> as.numeric(format(date1, "%Y"))
[1] 2012
See ?yearmon and ?strftime for details - the latter explains the placeholder characters you can use.
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How do CDI and EJB compare? interact?
I'm having a tough time understanding how the two interact and where the boundary between them lies. Do they overlap? Are there redundancies between them?
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Force R not to use exponential notation (e.g. e+10)?
...a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied when deciding to print
numeric value...
How to tell if a string is not defined in a Bash shell script
...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
Java compiler level does not match the version of the installed Java project facet
...you are using the m2e plugin in Eclipse, you'll need to specify the source and target versions as 1.6 for maven-compiler-plugin. m2e uses these values to determine the project's Java compiler level. A snippet of the POM is shown below:
<build>
<plugins>
<plugin>
<ar...
How to do paging in AngularJS?
I have a dataset of about 1000 items in-memory and am attempting to create a pager for
this dataset, but I'm not sure on how to do this.
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Can I assume (bool)true == (int)1 for any C++ compiler?
...are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.
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How to generate a range of numbers between two numbers?
I have two numbers as input from the user, like for example 1000 and 1050 .
28 Answers
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Copy a table from one database to another in Postgres
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Extract the table and pipe it directly to the target database:
pg_dump -t table_to_copy source_db | psql target_db
Note: If the other database already has the table set up, you should use the -a flag to import data only, else you may see we...