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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
Scala @ operator
...n itself? That would be accomplished with this:
o match {
case x @ Some(_) => println(x)
case None =>
}
Note that @ can be used at any level, not just at the top level of the matching.
share
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Efficiently convert rows to columns in sql server
...d than just a single script but gives you much more flexibility.
First of all There are 3 objects:
User defined TABLE type [ColumnActionList] -> holds data as
parameter
SP [proc_PivotPrepare] -> prepares our data
SP [proc_PivotExecute] -> execute the script
CREATE TYPE [dbo].[ColumnAc...
How to sort with a lambda?
...nclude <iostream>
#include <sstream>
struct Foo
{
Foo() : _i(0) {};
int _i;
friend std::ostream& operator<<(std::ostream& os, const Foo& f)
{
os << f._i;
return os;
};
};
typedef std::vector<Foo> VectorT;
std::string ...
Convert Python dictionary to JSON array
...
If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
querySelector, wildcard element match?
...to do a wildcard element name match using querySelector or querySelectorAll ? I see support for wildcards in attribute queries but not for the elements themselves.
...
Returning value from called function in a shell script
I want to return the value from a function called in a shell script. Perhaps I am missing the syntax. I tried using the global variables. But that is also not working. The code is:
...
CORS - How do 'preflight' an httprequest?
...t involves configuring the server responses to include the "Access-Control-Allow-Origin" header and 'preflight' requests with and OPTIONS request. I got the idea from this post : Getting CORS working
...
Making 'git log' ignore changes for certain paths
...e as match_pathspec_depth_1() and for correctness was only supposed to be called from match_pathspec_depth(). match_pathspec_depth() was later renamed to match_pathspec(), so the invariant we expect today is that do_match_pathspec() has no direct callers outside of match_pathspec().
Unfortunately,...
onCreateOptionsMenu inside Fragments
...nsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_sample, menu);
super.onCreateOptionsMenu(menu,inflater);
}
And in onCreate add this line to make the options appear in your Toolbar
setHasOptionsMenu(true);
...