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Remove duplicated rows using dplyr
... @hadley I like the unique() and distinct() function, however, they all remove the 2nd duplicate from the data frame. what if I want to have all 1st encounters of the duplicate value removed? How could this be done? Thanks for any help!
– FlyingDutch
Feb...
Forced naming of parameters in Python
...(10, forcenamed=20)
10 20
>>> foo(10, 20)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: foo() takes exactly 1 positional argument (2 given)
This can also be combined with **kwargs:
def foo(pos, *, forcenamed, **kwargs):
...
Can I run javascript before the whole page is loaded?
... script execution is complete (because the script might do document.write calls to output markup that the parser should handle).
That's the default behavior, but you have a few options for delaying script execution:
Use JavaScript modules. A type="module" script is deferred until the HTML has bee...
How to pass macro definition from “make” command line arguments (-D) to C source code?
I usually pass macro definitions from "make command line" to a "makefile" using the option :
-Dname=value. The definition is accessible inside the makefile.
...
ReactJS: Modeling Bi-Directional Infinite Scrolling
...following:
Overview
Make a <List> component that takes an array of all children. Since we do not render them, it's really cheap to just allocate them and discard them. If 10k allocations is too big, you can instead pass a function that takes a range and return the elements.
<List>
{...
How do I script a “yes” response for installing programs?
...mazon Linux instances and I have a couple scripts to populate data and install all the programs I work with, but a couple of the programs ask:
...
What's the meaning of Base SDK, iOS deployment target, Target, and Project in xcode
...ect can have multiple targets and you might not want the same settings for all targets. The project-level settings override the default settings and the target-level settings override the project-level settings.
For example I have projects with both OSX and iOS targets and some are ARC and some ar...
Best way to use PHP to encrypt and decrypt passwords? [duplicate]
...ing. You should not rely on unauthenticated encryption for security, especially since the code as provided is vulnerable to padding oracle attacks.
See also:
https://stackoverflow.com/a/30189841/2224584
https://stackoverflow.com/a/30166085/2224584
https://stackoverflow.com/a/30159120/2224584
Al...
How to RSYNC a single file?
... anywhere on the server by just specifying it's path? The man page isn't really clear about that.
– user1115652
Jun 18 '16 at 9:11
2
...
The Concept of 'Hold space' and 'Pattern space' in sed
... line. So what happens is this:
first line is read and inserted automatically into the pattern space
on the first line, first command is not executed; h copies the first line into the hold space.
now the second line replaces whatever was in the pattern space
on the second line, first we execute G,...