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How to convert a data frame column to numeric type?
... that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
fac = factor(1:5),
...
MySQL: multiple tables or one table with many columns?
...r if I separate the tables in this manner to improve the performance? I'll now go read about the wiki that you mentioned :)
– Xavier_Ex
Mar 19 '12 at 17:45
...
Difference between await and ContinueWith
...ere. If you don't specify where you want the continuation to run, I don't know what the default is but it could easily end up running on a thread pool thread... at which point you can't access the UI, etc.
– Jon Skeet
Sep 23 '13 at 19:59
...
How to apply specific CSS rules to Chrome only?
...https://jeffclayton.wordpress.com/2015/08/10/1279/
/* Chrome, Safari, AND NOW ALSO the Edge Browser and Firefox */
@media and (-webkit-min-device-pixel-ratio:0) {
div{top:10;}
}
/* Chrome 29+ */
@media screen and (-webkit-min-device-pixel-ratio:0)
and (min-resolution:.001dpcm) {
div{top:0...
List of Delphi language features and version in which they were introduced/deprecated
... bit AnsiChar/AnsiString support in enable on Linux.
C++Builder and Delphi now use the same ABI for all calls.
Delphi 10.2 Tokyo
Support for Linux server apps (Intel 64-bit using LLVM and ARC).
Assigning a dynamic arrays to a pointer using the @ operator is only allowed when hard-casting the a...
git merge: apply changes to code that moved to a different file
I am attempting a pretty beefy git merge maneuver right now. One problem that I am coming across is that I made some changes to some code in my branch, but my colleague moved that code to a new file in his branch. So when I did git merge my_branch his_branch , git did not notice that the code in ...
Convert timedelta to total seconds
...= time.time(); print tt
1301736663.88
>>> print datetime.datetime.now()
2011-04-02 20:31:03.882000 ### UTC+11, my local time
>>> print datetime.datetime(1970,1,1) + datetime.timedelta(seconds=tt)
2011-04-02 09:31:03.880000 ### UTC
>>> print time.localtime()
time.struct_tim...
structure vs class in swift language
...e is changed, the instance referenced by both variables is updated. Bob is now Sue, everywhere that Bob was ever referenced.
class SomeClass {
var name: String
init(name: String) {
self.name = name
}
}
var aClass = SomeClass(name: "Bob")
var bClass = aClass // aClass and bClass...
How to launch Safari and open URL from iOS app
...erstood this but if I am opening a website and user is surfing the website now if he stops by a particular page then can I get the current webpage link in my code?
– Varun Jain
Jun 1 '16 at 7:33
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How do you use “git --bare init” repository?
...
useful if you want to know difference between bare and non-bare repos stackoverflow.com/questions/7861184/…
– Guille Acosta
Mar 7 '16 at 14:52
...