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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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Shorten string without cutting words in JavaScript
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Lodash has a function specifically written for this: _.truncate
const truncate = _.truncate
const str = 'The quick brown fox jumps over the lazy dog'
truncate(str, {
length: 30, // maximum 30 characters
separator: /,?\.* +/ // separate by spaces, including preceding comma...
MySQL string replace
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Quick question, is it really needed to have the "WHERE" clause?
– John Crawford
Jul 17 '13 at 8:08
58
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Manually adding a Userscript to Google Chrome
Instead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
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Difference between this and self in self-type annotations?
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All three forms are valid, and have the effect that B is assumed as the type of this in class A.
The first two variants
trait A { self: B => ... }
trait A { foo: B => ... }
introduce self (respectively, foo) as an ...
Print function log /stack trace for entire program using firebug
Firebug has the ability to log calls to a particular function name. I'm looking for a bug that sometimes stops a page from rendering, but doesn't cause any errors or warnings. The bug only appears about half the time. So how do I get a list of all the function calls for the entire program, or som...
SQL Server SELECT INTO @variable?
... In case if you aren't using the database type that the OP is using, not all support TOP 1 as Adrian mentioned. SQL Server / MS Access use TOP, MySQL uses LIMIT, and Oracle uses ROWNUM. See w3schools.com/sql/sql_top.asp for more information.
– Tyler
Jul 7 '17...
What are all the common undefined behaviours that a C++ programmer should know about? [closed]
What are all the common undefined behaviours that a C++ programmer should know about?
11 Answers
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Append to a file in Go
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This answers works in Go1:
f, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
if err != nil {
panic(err)
}
defer f.Close()
if _, err = f.WriteString(text); err != nil {
panic(err)
}
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Correct way to define Python source code encoding
...f you want to be 100% python-docs-recommendation-compatible.
More specifically, you need to use whatever is recognized by Python and the specific editing software you use (if it needs/accepts anything at all). E.g. the coding form is recognized (out of the box) by GNU Emacs but not Vim (yes, withou...