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Returning multiple objects in an R function [duplicate]
...and a vector of strings bar in your function, you could create a list that combines these items:
foo <- 12
bar <- c("a", "b", "e")
newList <- list("integer" = foo, "names" = bar)
Then return this list.
After calling your function, you can then access each of these with newList$integer ...
Highlight text similar to grep, but don't filter out text [duplicate]
...g full perl regular expressions.
$ ack --passthru 'pattern1' file_name
$ command_here | ack --passthru 'pattern1'
You can also do it using grep like this:
$ grep --color -E '^|pattern1|pattern2' file_name
$ command_here | grep --color -E '^|pattern1|pattern2'
This will match all lines and hi...
MySQL: Fastest way to count number of rows
...tely after the data selecting query.
In conclusion, everything actually comes down to how many entries you have and what is in the WHERE statement. You should really pay attention on how indexes are being used, when there are lots of rows (tens of thousands, millions, and up).
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When saving, how can you check if a field has changed?
...stead of overwriting init, I'd use the post_init-signal docs.djangoproject.com/en/dev/ref/signals/#post-init
– vikingosegundo
Nov 24 '09 at 22:43
24
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In PyCharm, how to go back to last location?
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Under ArchLinux with PyCharm CE 3.1 works the combination Ctrl + Alt + Left.
This is the way I find out the combination:
(Right click) Go To -> Implementation(s)
Double Shift -> Back
There is an option Back in the section Actions
Ctrl + Shift + A
And then the ...
Possible to iterate backwards through a foreach?
... UPDATE: See [Bryan's answer to a similar question[(stackoverflow.com/a/3320924/199364), for a more modern answer, using Linq, and discussing both lists, and other enumerables.
– ToolmakerSteve
Mar 2 '17 at 20:28
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Best practices to handle routes for STI subclasses in rails
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This is the simplest solution I was able to come up with with minimal side effect.
class Person < Contact
def self.model_name
Contact.model_name
end
end
Now url_for @person will map to contact_path as expected.
How it works: URL helpers rely on YourModel...
Test for existence of nested JavaScript object key
...9-10-17:
The optional chaining proposal reached Stage 3 on the ECMAScript committee process, this will allow you to safely access deeply nested properties, by using the token ?., the new optional chaining operator:
const value = obj?.level1?.level2?.level3
If any of the levels accessed is null ...
When NOT to use Cassandra?
...almost the same kind of solutions oriented toward ACID properties. When it comes to NoSQL, the decision becomes difficult because every NoSQL database offers different solutions and you have to understand which one is best suited for your app/system requirements. For example, MongoDB is fit for use...
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo
... I have a class which does not extends activity, just contains some common fuctions; but i still get this exception; why?
– Manoj Kumar
Sep 10 '12 at 8:09
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