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Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
... to the process in question using gdb, and run:
p dup2(open("/dev/null", 0), 1)
p dup2(open("/dev/null", 0), 2)
detach
quit
e.g.:
$ tail -f /var/log/lastlog &
[1] 5636
$ ls -l /proc/5636/fd
total 0
lrwx------ 1 myuser myuser 64 Feb 27 07:36 0 -> /dev/pts/0
lrwx------ 1 myuser myuser 6...
How to assign string to bytes array
...ices in Go is using a slice of bytes []byte and not a set array of bytes [20]byte when converting a string to bytes... Don't believe me? Check out Rob Pike's answer on this thread
– openwonk
Feb 14 '16 at 0:44
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OAuth: how to test with local URLs?
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Update October 2016: Easiest now: use lvh.me which always points to 127.0.0.1.
Previous Answer:
Since the callback request is issued by the browser, as a HTTP redirect response, you can set up your .hosts file or equivalent to point a domain...
Change the Right Margin of a View Programmatically?
...arams = (LinearLayout.LayoutParams)tv.getLayoutParams();
params.setMargins(0, 0, 10, 0); //substitute parameters for left, top, right, bottom
tv.setLayoutParams(params);
I can't test it right now, so my casting may be off by a bit, but the LayoutParams are what need to be modified to change the mar...
CSS: bolding some text without changing its container's size
...h a little compromise, I used text-shadow instead.
li:hover {text-shadow:0px 0px 1px black;}
Here's a working example:
body {
font-family: segoe ui;
}
ul li {
display: inline-block;
border-left: 1px solid silver;
padding: 5px
}
.textshadow :hover {
text-shadow: 0px 0p...
What's the idiomatic syntax for prepending to a short python list?
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The s.insert(0, x) form is the most common.
Whenever you see it though, it may be time to consider using a collections.deque instead of a list.
share
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How to remove the querystring and get only the url?
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+100
You can use strtok to get string before first occurence of ?
$url = strtok($_SERVER["REQUEST_URI"], '?');
strtok() represents the ...
Regex how to match an optional character
...e letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})
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Why does Decimal.Divide(int, int) work, but not (int / int)?
How come dividing two 32 bit int numbers as ( int / int ) returns to me 0 , but if I use Decimal.Divide() I get the correct answer? I'm by no means a c# guy.
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