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How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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abort, terminate or exit?
What's the difference between those three, and how shall I end program in case of exception which I can't handle properly?
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Vim: What's the difference between let and set?
...iendly interface specialized for options
E.g.
:verbose set
to display all options in effect.
:set tw=40
Will work as a shorthand for set textwidth=40
:set wrap&
Will set the default value for option wrap
:set nowrap
Will unset the option
:set wrap!
Will toggle the option
Most i...
How to make an introduction page with Doxygen
...tation - very useful for documentation that is necessary but that is not really appropriate to include with your source code (for example, an FAQ)
So I would recommend having a mainpage.dox (or similarly named) file in your project directory to introduce you SDK. Note that inside this file you need...
Resizing UITableView to fit content
...
Actually I found the answer myself.
I just create a new CGRect for the tableView.frame with the height of table.contentSize.height
That sets the height of the UITableView to the height of its content.
Since the code modifies th...
How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i
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Just another warning. aes_string does not allow you to use functions to manipulate the x and y values. Say that you would like to log transform y in which case aes_string(x = 'x.values', y='log(y.values)') of course doesn't work. I use these kind of transformations a...
java.lang.UnsupportedClassVersionError: Bad version number in .class file?
...n I include an opensource library that I had to compile from source. Now, all the suggestions on the web indicate that the code was compiled in one version and executed in another version (new on old). However, I only have one version of JRE on my system. If I run the commands:
...
When and why to 'return false' in JavaScript?
...s, such as onsubmit, returning false is a way to tell the event to not actually fire. So, say, in the onsubmit case, this would mean that the form is not submitted.
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How to get the next auto-increment id in mysql
... Thanks for the first two options.. But the third is just number two called from PHP.. Not sure what makes that faster on large databases...
– Gerard ONeill
Feb 12 '16 at 15:26
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How to get current timestamp in string format in Java? “yyyy.MM.dd.HH.mm.ss”
... Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
Later versions of Androi...