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Why is `[` better than `subset`?
When I need to filter a data.frame, i.e., extract rows that meet certain conditions, I prefer to use the subset function:
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How to use a variable to specify column name in ggplot
...<- function( column ) {
...
ggplot( rates.by.groups, aes_string(x="name", y="rate", colour= column,
group=column ) )
}
as long as you pass the column to the function as a string (f("majr") rather than f(majr)). Also note that we changed the other ...
Get the full URL in PHP
...TP_HOST]$_SERVER[REQUEST_URI]";
(Note that the double quoted string syntax is perfectly correct)
If you want to support both HTTP and HTTPS, you can use
$actual_link = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_UR...
fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'
...ficiency of cuda. I think the library files linked are all compiled on the x86 platform, but when I compile it, I get the error message "fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'".
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Why is the apt-get function not working in the terminal on Mac OS X v10.9 (Mavericks)?
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Mac OS X doesn't have apt-get. There is a package manager called Homebrew that is used instead.
This command would be:
brew install python
Use Homebrew to install packages that you would otherwise use apt-get for.
The page I linke...
Formatting Decimal places in R
I have a number, for example 1.128347132904321674821 that I would like to show as only two decimal places when output to screen (or written to a file). How does one do that?
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SQL Query Where Field DOES NOT Contain $x
I want to find an SQL query to find rows where field1 does not contain $x. How can I do this?
2 Answers
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Remove duplicates in the list using linq
...temComparer : IEqualityComparer<Item> {
public bool Equals(Item x, Item y) {
return x.Id == y.Id &&
x.Name == y.Name &&
x.Code == y.Code &&
x.Price == y.Price;
}
public int GetHashCode(Item obj) {
return ...
Factors in R: more than an annoyance?
One of the basic data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something.
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