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In R, how to get an object's name after it is sent to a function?
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The old deparse-substitute trick:
a<-data.frame(x=1:10,y=1:10)
test<-function(z){
mean.x<-mean(z$x)
nm <-deparse(substitute(z))
print(nm)
return(mean.x)}
test(a)
#[1] "a" ... this is the side-effect of the print() call
# ... you could have done...
How do I remove the passphrase for the SSH key without having to create a new key?
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2034
Short answer:
$ ssh-keygen -p
This will then prompt you to enter the keyfile location, the ...
What does “all” stand for in a makefile?
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answered Mar 25 '10 at 11:26
P ShvedP Shved
83.1k1414 gold badges113113 silver badges160160 bronze badges
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Is having an 'OR' in an INNER JOIN condition a bad idea?
...ed of an immensely slow query (several minutes on two tables with only ~50,000 rows each, on SQL Server 2008 if it matters), I narrowed down the problem to an OR in my inner join, as in:
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What's the difference between belongs_to and has_one?
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answered Sep 28 '10 at 0:53
ryeguyryeguy
58.7k4949 gold badges181181 silver badges254254 bronze badges
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ASP.Net MVC Html.HiddenFor with wrong value
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Darin DimitrovDarin Dimitrov
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Which timestamp type should I choose in a PostgreSQL database?
... a user’s time zone as a user preference (e.g. America/Los_Angeles, not -0700).
Have user events/time data submitted local to their frame of reference (most likely an offset from UTC, such as -0700).
In application, convert the time to UTC and stored using a TIMESTAMP WITH TIME ZONE column.
Return...
How to center the content inside a linear layout?
..._parent"
android:layout_height="match_parent"
android:background="#000"
android:baselineAligned="false"
android:gravity="center"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/ac...
Validate uniqueness of multiple columns
...be patched?
– Alexey
Jul 16 '12 at 20:09
13
Alexey, validates_uniqueness_of [:user_id, :friend_id...
Difference between database and schema
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Mar 16 '11 at 10:11
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