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Why is `[` better than `subset`?
...eval(expr, envir, enclos) : object 'cyl' not found
because R no longer "knows" where to find the object called 'cyl'. He also points out the truly bizarre stuff that can happen if by chance there is an object called 'cyl' in the global environment:
cyl <- 4
subscramble(mtcars, cyl == 4)
cyl &...
How to set a bitmap from resource
... R.drawable.android_logo
);
Now you can use this bitmap object, whether you want to store it, or to use it in google maps while drawing a pic on fixed latitude and longitude, or to use some where else
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How to find if directory exists in Python
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@CamilStaps This question was viewed 354000 times (by now). Answers here are not only for OP, they are for anyone who could come here for whatever reason. aganders3's answer is pertinent even if it does not directly resolve OP's problem.
– Gabriel
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jQuery see if any or no checkboxes are selected
I know how to see if an individual checkbox is selected or not.
8 Answers
8
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Is mongodb running?
... quickly checking if mongodb is running, this quick nc trick will let you know.
nc -zvv localhost 27017
The above command assumes that you are running it on the default port on localhost.
For auto-starting it, you might want to look at this thread.
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Supervisor socket error issue [closed]
...c/supervisord.conf /etc/supervisor/supervisord.conf
if you want to keep it
Now you can run sudo supervisorctl
Why?
when you run supervisorctl it first searches for the config file located at /etc/supervisord.conf, if it's not present, it will search for the package's default file /etc/supervisor/su...
Load data from txt with pandas
...ng data. I want to store them in an array where I can access each element. Now I am just doing
9 Answers
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Create, read, and erase cookies with jQuery [duplicate]
...ileNotFound" (or something close to that, I'm not at my dev computer right now). Thanks!
– jackerman09
Sep 27 '13 at 18:24
8
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How do CSS triangles work?
... this:
But there's no need for the top border, so set its width to 0px. Now our border-bottom of 200px will make our triangle 200px tall.
.triangle {
border-color: yellow blue red green;
border-style: solid;
border-width: 0px 200px 200px 200px;
height: 0px;
width: 0px;
}
an...
What is difference between functional and imperative programming languages?
... see how anyone could read this answer and come away feeling confident in knowing the difference between declarative and procedural programming.
– Ringo
Apr 24 '17 at 7:02
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