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Android: how to make keyboard enter button say “Search” and handle its click?
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answered Mar 16 '17 at 8:50
kaMChykaMChy
34133 silver badges66 bronze badges
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Grouping functions (tapply, by, aggregate) and the *apply family
...] 1
$b
[1] 3
$c
[1] 91
lapply(x, FUN = sum)
$a
[1] 1
$b
[1] 6
$c
[1] 5005
sapply - When you want to apply a function to each element of a
list in turn, but you want a vector back, rather than a list.
If you find yourself typing unlist(lapply(...)), stop and consider
sapply.
x <- list(a =...
UIView frame, bounds and center
...ew. For example:
UIView* view1 = [[UIView alloc] initWithFrame:CGRectMake(50.0f, 50.0f, 400.0f, 400.0f)];
view1.backgroundColor = [UIColor redColor];
UIView* view2 = [[UIView alloc] initWithFrame:CGRectInset(view1.bounds, 20.0f, 20.0f)];
view2.backgroundColor = [UIColor yellowColor];
[vie...
Assign multiple columns using := in data.table, by group
...t to the dt.
– Jfly
Aug 5 '18 at 19:50
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show 9 more comme...
Find integer index of rows with NaN in pandas dataframe
...l(df).any(1).nonzero()[0]
In [9]: df
Out[9]:
0 1
0 0.450319 0.062595
1 -0.673058 0.156073
2 -0.871179 -0.118575
3 0.594188 NaN
4 -1.017903 -0.484744
5 0.860375 0.239265
6 -0.640070 NaN
7 -0.535802 1.632932
8 0.876523 -0.153634
9 -0.686914 0.131185
In [10]: p...
Get last field using awk substr
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edited Dec 20 '16 at 13:50
answered Jul 29 '13 at 10:25
f...
What is the Sign Off feature in Git for?
...ecifically the first sentence). As a counter-example, see for example b2c150d3aa (linked to in VonC’s answer), which has two signed-off-by headers; one by the author, and one by the maintainer. This is common practice in the Git and Linux projects.
– Guildenstern
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What is “point free” style (in Functional Programming)?
...urrying?
– kaleidic
Oct 2 '10 at 22:50
1
@kaleidic: Because without having variable names, you ne...
Does .NET have a way to check if List a contains all items in List b?
...hm?
– Colonel Panic
Jan 5 '16 at 16:50
1
@ColonelPanic: Assuming no hash collisions, O(n+m).
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How do I center an SVG in a div?
...se answers worked for me. This is how I did it.
position: relative;
left: 50%;
-webkit-transform: translateX(-50%);
-ms-transform: translateX(-50%);
transform: translateX(-50%);
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