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Difference between dict.clear() and assigning {} in Python
...ing methods are always useful if the original object is not in scope:
def fun(d):
d.clear()
d["b"] = 2
d={"a": 2}
fun(d)
d # {'b': 2}
Re-assigning the dictionary would create a new object and wouldn't modify the original one.
...
Remove columns from dataframe where ALL values are NA
...nswered May 14 '19 at 21:48
André.BAndré.B
30433 silver badges1414 bronze badges
...
One-liner to check whether an iterator yields at least one element?
... Thanks, I think I'm going to use next().
– Bastien Léonard
Jun 24 '10 at 23:07
1
@Bastien, fine...
How can you tell when a layout has been drawn?
...n pixels of the parent layout object. But during the onCreate and onResume functions, the Layout has not been drawn yet, and so layout.getMeasuredHeight() returns 0.
...
What's the reason I can't create generic array types in Java?
...r second example may throw a ClassCastException
– José Roberto Araújo Júnior
Jan 31 '14 at 2:27
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How to select the row with the maximum value in each group
...
The most intuitive method is to use group_by and top_n function in dplyr
group %>% group_by(Subject) %>% top_n(1, pt)
The result you get is
Source: local data frame [3 x 3]
Groups: Subject [3]
Subject pt Event
(dbl) (dbl) (dbl)
1 ...
How can I combine flexbox and vertical scroll in a full-height app?
...answered Feb 19 '13 at 18:38
José CaboJosé Cabo
3,99933 gold badges2020 silver badges3131 bronze badges
...
How do I set default values for functions parameters in Matlab?
... use "varargs" and check against the number of arguments. Something like:
function f(arg1, arg2, arg3)
if nargin < 3
arg3 = 'some default'
end
end
There are a few fancier things you can do with isempty, etc., and you might want to look at Matlab central for some packages that bundl...
Reflection - get attribute name and value on property
... very nice and useful answer to many cases.
– David Létourneau
Jan 14 '16 at 16:26
1
Thanks @Dav...
How to break out of nested loops?
...
No, don't spoil the fun with a break. This is the last remaining valid use of goto ;)
If not this then you could use flags to break out of deep nested loops.
Another approach to breaking out of a nested loop is to factor out both loops into ...