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R apply function with multiple parameters
...ctor variables and must compute itself on each value of them (as mentioned by @Ari B. Friedman) you can use mapply as follows:
vars1<-c(1,2,3)
vars2<-c(10,20,30)
mult_one<-function(var1,var2)
{
var1*var2
}
mapply(mult_one,vars1,vars2)
which gives you:
> mapply(mult_one,vars1,vars2...
In Postgresql, force unique on combination of two columns
...is case. From the PostgeSQL docs: "Note that a unique constraint does not, by itself, provide a unique identifier because it does not exclude null values.)" postgresql.org/docs/8.1/static/ddl-constraints.html#AEN2038
– ndequeker
Feb 3 '17 at 13:53
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Positive Number to Negative Number in JavaScript?
...
Is this faster than multiplying by negative 1?
– ryandawkins
Jun 2 '15 at 15:32
...
How to extract a string using JavaScript Regex?
...multiple lines (i.e., match the beginning or end of each line
(delimited by \n or \r), not only the very beginning or end of the
whole input string)
Also put the * in the right place:
"DATE:20091201T220000\r\nSUMMARY:Dad's birthday".match(/^SUMMARY\:(.*)$/gm);
//------------------------------...
Private and protected constructor in Scala
...
You can declare the default constructor as private/protected by inserting the appropriate keyword between the class name and the parameter list, like this:
class Foo private () {
/* class body goes here... */
}
...
ASP.NET Temporary files cleanup
...pPlace" />
I even have a funky setup at work where we don't run Admin by default, plus the IT guys have login scripts that set %temp% and I get temp files in 3 different locations depending on what is compiling things! And I'm still not certain about how these paths get picked....sigh.
Still,...
Open a file with Notepad in C#
How I open a file in c#? I don't mean reading it by textreader and readline(). I mean open it as an independent file in notepad.
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How to encode URL parameters?
...
What do you mean by "except for your browser handling the compatibility"?
– Stephan
Jul 31 at 6:12
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How can the Euclidean distance be calculated with NumPy?
... - b
numpy.sqrt(numpy.einsum('ij,ij->j', a_min_b, a_min_b))
which is, by a slight margin, the fastest variant. (That actually holds true for just one row as well.)
The variants where you sum up over the second axis, axis=1, are all substantially slower.
Code to reproduce the plot:
import...
Ruby: How to turn a hash into HTTP parameters?
..., "e"]}.to_query)
=> "a=a&b[]=c&b[]=d&b[]=e"
http://api.rubyonrails.org/classes/Object.html#method-i-to_query
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