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Extracting just Month and Year separately from Pandas Datetime column
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what actually does pd.Datetimeindex do?
– JOHN
Apr 16 '18 at 5:24
1
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Finding current executable's path without /proc/self/exe
...e) method is to use argv[0]. Although it could be set to anything by the calling program, by convention it is set to either a path name of the executable or a name that was found using $PATH.
Some shells, including bash and ksh, set the environment variable "_" to the full path of the executable be...
How do I write the 'cd' command in a makefile?
...
It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.
If you're looking to perform more tasks wit...
Is it a good practice to use an empty URL for a HTML form's action attribute? (action=“”)
...for compatibility with legacy content. [RFC3986]
This definitely works in all current browsers, but may not work as expected in some older browsers ("browsers do weird things with an empty action="" attribute"), which is why the spec strongly discourages authors from leaving it empty:
The action a...
How to add a 'or' condition in #ifdef
...¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|//
#ifdef CONDITION_01 //| |//
#define TEMP_MACRO //| |//
#endif //| |//
#ifdef CONDITION_02 //| |//
#define TEMP_MACRO //| |//
#endif ...
Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;
...ing the Java Build Path and seeing this new item, and unchecking the originally-included support library solved the problem for me.
– Tom Pace
Sep 26 '13 at 17:20
9
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Symfony 2: How do I check if a user is not logged in inside a template?
...any user is logged in.
{% if app.user %}
# user is logged in (any and all users, regardless of ROLE_*)
{% elseif not app.user %}
# user is not logged in (note the `not` in the `elseif` statement)
{% endif %}
Checking authentication status
You can use the is_granted() method to check fo...
How is the undo tree used in Vim?
...
See also :h undo-redo, which lists all the commands and their usage.
There are two ways to traverse the undo tree. One is to go "back in time". g+ and g- will traverse all of the nodes in the tree in chronological or reverse-chronological order (which can...
What does character set and collation mean exactly?
...a symbol, the number 0 is the
encoding for 'A', and the combination
of all four letters and their
encodings is a character set.
Now, suppose that we want to compare
two string values, 'A' and 'B'. The
simplest way to do this is to look at
the encodings: 0 for 'A' and 1 for
'B'. Be...
How do I get around type erasure on Scala? Or, why can't I get the type parameter of my collections?
...hese instances are objects, you can pass them around, store them, and generally call methods on them. With the support of implicit parameters, it becomes a very powerful tool. Take the following example, for instance:
object Registry {
import scala.reflect.Manifest
private var map= Map.empty[...