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Convert data.frame column format from character to factor
...r approach
mtcars[, 'cyl'] <- as.factor(mtcars[, 'cyl'])
str(mtcars) # now look at the classes
This also works for character, dates, integers and other classes
Since you're new to R I'd suggest you have a look at these two websites:
R reference manuals:
http://cran.r-project.org/manuals.html...
Get nodes where child node contains an attribute
...if title is not a direct child of book, but somewhere deeper and we don't know where exactly? //book[/title/@lang = 'it'] doesn't seem to work?
– Martin Konicek
Oct 28 '13 at 11:35
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Solutions for distributing HTML5 applications as desktop applications? [closed]
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Mozilla Prism is inactive now
– Harshith J.V.
Jun 25 '12 at 8:39
8
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Simulate delayed and dropped packets on Linux
... the local Ethernet.
# tc qdisc add dev eth0 root netem delay 100ms
Now a simple ping test to host on the local network should show an increase of 100 milliseconds. The delay is limited by the clock resolution of the kernel (Hz). On most 2.4 systems, the system clock runs at 100 Hz which all...
Python: print a generator expression?
...expression is a "naked" for expression. Like so:
x*x for x in range(10)
Now, you can't stick that on a line by itself, you'll get a syntax error. But you can put parenthesis around it.
>>> (x*x for x in range(10))
<generator object <genexpr> at 0xb7485464>
This is sometime...
Execute AsyncTask several times
...n onResume(). So i made my Asynctask static, and get the instance from it. Now we still have the same problem.
So what i did in the onPostExecute() is this:
instance = null;
Keeping in mind that i check in the static getInstance method that my instance isn't null, else i create it:
if (instanc...
Why would someone use WHERE 1=1 AND in a SQL clause?
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If the list of conditions is not known at compile time and is instead built at run time, you don't have to worry about whether you have one or more than one condition. You can generate them all like:
and <condition>
and concatenate them all together....
How do you simulate Mouse Click in C#?
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@Jez - Handy to know, thanks. Not seen any issues yet myself, but now I at least know some exist ;0)
– Rusty Nail
Oct 22 '18 at 1:05
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How do I ignore the initial load when watching model changes in AngularJS?
...ner'. I am using this watch to detect if the page/entity is "dirty". Right now I'm making the save button bounce but really I want to make the save button invisible until the user dirties the model.
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Create nice column output in python
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by far the best solution as of now
– zlr
Apr 18 '14 at 10:17
This only eve...