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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...
How can I get a precise time, for example in milliseconds in Objective-C?
...liseconds
// Use (-) modifier to conversion since receiver is earlier than now
double timePassed_ms = [date timeIntervalSinceNow] * -1000.0;
Documentation on timeIntervalSinceNow.
There are many other ways to calculate this interval using NSDate, and I would recommend looking at the class documen...
Why does this async action hang?
...elect slow running data into result"));
}
What's the difference? There's now no awaiting anywhere, so nothing being implicitly scheduled to the UI thread. For simple methods like these that have a single return, there's no point in doing an "var result = await...; return result" pattern; just remo...
How to git log in reverse order?
...s then reverses that list so the most recent of those 10 is at the bottom. Now you can simply run:
git lg
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What is the difference between char array and char pointer in C?
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Is something changed from 2012 to now. For a character array "s" prints entire array.. i.e., "hello"
– Bhanu Tez
May 9 '19 at 6:48
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Illegal mix of collations MySQL Error
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Seems to work for now, i'll accept after some more testing. Do the second queries need to be run once, or at the start of each script?
– Click Upvote
Jun 17 '09 at 19:06
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Java 8 Stream and operation on arrays
...va 8 stream capabilities. Coming from Python, I was wondering if there was now a neat way to do operations on arrays like summing, multiplying two arrays in a "one line pythonic" way ?
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Render HTML to PDF in Django site
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pisa is now distributed as xhtml2pdf
– Pablo Albornoz
Jun 6 '13 at 19:56
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Can I Set “android:layout_below” at Runtime Programmatically?
... While jackofallcode solution is the only right here, I simplified it. But now I think shortening to one line is not good, because if any exception occurs, it would be harder to understand what operator raised it.
– CoolMind
Nov 19 '18 at 6:54
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How to access test resources in Scala?
...urce.fromURL(getClass.getResource("/data.xml"))
Of course that source is now just a normal Scala IO object so you can do anything you want with it, like reading the contents and using it for test data.
There are other methods to get the resource as well (for example as a stream). For more informa...