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What is the correct way to get a subarray in Scala?
...ColumnB", "ColumnC")
val columns_original = original_array(0)
for (column_now <- columns_subset) {
sub_array += original_array.map{_(columns_original.indexOf(column_now))}
}
sub_array
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What are the “standard unambiguous date” formats for string-to-date conversion in R?
...here a better solution than needing to specify the format?
Yes, there is now (ie in late 2016), thanks to anytime::anydate from the anytime package.
See the following for some examples from above:
R> anydate(c("01 Jan 2000", "01/01/2000", "2015/10/10"))
[1] "2000-01-01" "2000-01-01" "2015-10...
What does the `#` operator mean in Scala?
...le example:
class A {
class B
def f(b: B) = println("Got my B!")
}
Now let's try something with it:
scala> val a1 = new A
a1: A = A@2fa8ecf4
scala> val a2 = new A
a2: A = A@4bed4c8
scala> a2.f(new a1.B)
<console>:11: error: type mismatch;
found : a1.B
required: a2.B
...
Is it valid to have a html form inside another html form?
...he problem with using such approaches is that the behavior of your code is now not guaranteed across browsers. (since it's not standard)
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Adding new column to existing DataFrame in Python pandas
... did it wrong (it can trigger false positives) but from 0.13.0 it let you know there are more adequate methods for the same purpose. Then, if you get the warning, just follow its advise: Try using .loc[row_index,col_indexer] = value instead
>>> df1.loc[:,'f'] = pd.Series(np.random.randn(sL...
How can I make Bootstrap columns all the same height?
...er screens before the columns stack vertically)
Bootstrap 4
Flexbox is now used by default in Bootstrap 4 so there is no need for the extra CSS to make equal height columns: http://www.codeply.com/go/IJYRI4LPwU
Example:
<div class="container">
<div class="row">
<div ...
How to undo 'git reset'?
...ned by checking out a particular commit (though that's not important right now). So, to undo the reset, run git reset HEAD@{1} (or git reset d27924e).
If, on the other hand, you've run some other commands since then that update HEAD, the commit you want won't be at the top of the list, and you'll n...
JavaScript moving element in the DOM
...his in 2014, please consider this answer. jQuery WAS useful back then, but now it's no so useful anymore, because browsers are standardized, so no need to add a 80 kb library just to do such a simple task. Also, you don't get to know what the DOM really is until you try it without jQuery :)
...
How do I create a unique constraint that also allows nulls?
...won't let me store NULLs in a unique column in the first place. If anyone knows a solution for that, please post it here
– dotNET
Feb 2 '15 at 22:01
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What is JavaScript garbage collection?
...me
into scope and off the scav list when
they go out of scope.
Every now and then the garbage
collector runs. First it puts a
"mark" on every object, variable,
string, etc – all the memory tracked
by the GC. (JScript uses the VARIANT
data structure internally and there
are ple...