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Omit rows containing specific column of NA
... put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data[completeVec, ])
}
completeFun(DF, "y")
# x y z
# 1 1 0 NA
# 2 2 10 33
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How to tell whether a point is to the right or left side of a line
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204
Use the sign of the determinant of vectors (AB,AM), where M(X,Y) is the query point:
position ...
Socket File “/var/pgsql_socket/.s.PGSQL.5432” Missing In Mountain Lion (OS X Server)
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20 Answers
20
Active
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What is “rvalue reference for *this”?
...t;
t.f(); // lvalue
test().f(); // rvalue
}
Output:
$ clang++ -std=c++0x -stdlib=libc++ -Wall -pedantic t.cpp
$ ./a.out
lvalue object
rvalue object
The whole thing is done to allow you to take advantage of the fact when the object the function is called on is an rvalue (unnamed temporary, for ...
How to request Administrator access inside a batch file
...REM --> If error flag set, we do not have admin.
if '%errorlevel%' NEQ '0' (
echo Requesting administrative privileges...
goto UACPrompt
) else ( goto gotAdmin )
:UACPrompt
echo Set UAC = CreateObject^("Shell.Application"^) > "%temp%\getadmin.vbs"
set params= %*
echo UAC.S...
StringUtils.isBlank() vs String.isEmpty()
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407
StringUtils.isBlank() checks that each character of the string is a whitespace character (or th...
How to return PDF to browser in MVC?
... line in your controller action would be something like:
return File("Chap0101.pdf", "application/pdf");
If you are generating this PDF dynamically, it may be better to use a MemoryStream, and create the document in memory instead of saving to file. The code would be something like:
Document doc...
vertical align middle in
I want to keep the height of #abc div at 50px and text to align vertically in the middle of the div .
10 Answers
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How can I convert byte size into a human-readable format in Java?
...matting byte size to human readable format | Programming.Guide
SI (1 k = 1,000)
public static String humanReadableByteCountSI(long bytes) {
if (-1000 < bytes && bytes < 1000) {
return bytes + " B";
}
CharacterIterator ci = new StringCharacterIterator("kMGTPE");
...