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Android Studio: how to remove/update the “Created by” comment added to all new classes?
By default Android Studio automatically adds a header comment to all new classes, e.g.
9 Answers
...
Why is rbindlist “better” than rbind?
...w where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble converting long list of data.frames (~1 million) to single data.frame using do.call and ldply
These have benchmarks that show how fast it can be.
rbind.data.frame is slow, for a reason
rbind.data.frame do...
How can I specify a branch/tag when adding a Git submodule?
...ame thing except you can make changes to it.
– deadbabykitten
Feb 2 '16 at 0:13
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How can I escape a double quote inside double quotes?
...hell:
$ echo 'abc'\''abc'
abc'abc
$ echo "abc"\""abc"
abc"abc
It's done by finishing an already-opened one ('), placing the escaped one (\'), and then opening another one (').
Alternatively:
$ echo 'abc'"'"'abc'
abc'abc
$ echo "abc"'"'"abc"
abc"abc
It's done by finishing already opened one ('...
Tricks to manage the available memory in an R session
...of an interactive R session? I use the functions below [based on postings by Petr Pikal and David Hinds to the r-help list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effective solution was ... to run under 64-bit Linux with ample...
Get top n records for each group of grouped results
... for each group:
(
select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this article to determine the best route for your situation:
ht...
Is there a way to access the “previous row” value in a SELECT statement?
...
SQL has no built in notion of order, so you need to order by some column for this to be meaningful. Something like this:
select t1.value - t2.value from table t1, table t2
where t1.primaryKey = t2.primaryKey - 1
If you know how to order things but not how to get the previous val...
Data Modeling with Kafka? Topics and Partitions
... a topic is a grouping of messages of a similar type that will be consumed by the same type of consumer so in the example above, I would just have a single topic and if you´ll decide to push some other kind of data through Kafka, you can add a new topic for that later.
Topics are registered in Zoo...
Display two files side by side
How can 2 unsorted text files of different lengths be display side by side (in columns) in a shell
9 Answers
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Convert tabs to spaces in Notepad++
...ings->Preferences...->Tab Settings (previous versions)
Check Replace by space
(Optional) You can set the number of spaces to use in place of a Tab by changing the Tab size field.
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