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How to pass optional arguments to a method in C++?
... else
do_something_else();
}
you can call myfunc in both ways and both are valid
myfunc(10); // Mode will be set to default 0
myfunc(10, 1); // Mode will be set to 1
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impr...
Clear android application user data
...e for other apps, since it is store in private_mode. So executing this command could probalby only work on rooted devices. Otherwise you should try another approach.
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What does the “map” method do in Ruby?
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The map method takes an enumerable object and a block, and runs the block for each element, outputting each returned value from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Range are enume...
PHP: How to check if image file exists?
.../'.$filename)) {
… }
Also, make sure $filename is properly validated. And then, it will only work when allow_url_fopen is activated in your PHP config
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What does ':' (colon) do in JavaScript?
I'm learning JavaScript and while browsing through the jQuery library I see : (colon) being used a lot. What is this used for in JavaScript?
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PHP - find entry by object property from an array of objects
...;ID) {
$item = $struct;
break;
}
}
See this question and subsequent answers for more information on the latter - Reference PHP array by multiple indexes
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typecast string to integer - Postgres
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You can even go one further and restrict on this coalesced field such as, for example:-
SELECT CAST(coalesce(<column>, '0') AS integer) as new_field
from <table>
where CAST(coalesce(<column>, '0') AS integer) >= 10;
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Selecting only numeric columns from a data frame
...list-apply functions:
nums <- unlist(lapply(x, is.numeric))
Then standard subsetting
x[ , nums]
## don't use sapply, even though it's less code
## nums <- sapply(x, is.numeric)
For a more idiomatic modern R I'd now recommend
x[ , purrr::map_lgl(x, is.numeric)]
Less codey, less ref...
SSH to Vagrant box in Windows?
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And then do that for every VM in Vagrant. You know, Vagrant works with multiple VM's. So, just use the proper solution, not workaround: there is my answer below. Small patch in Vagrant.
– Michael Field
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What is the inverse function of zip in python? [duplicate]
I've used the zip() function from the numpy library to sort tuples and now I have a list containing all the tuples. I had since modified that list and now I would like to restore the tuples so I can use my data. How can I do this?
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