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Can we use join for two different database tables?
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2 Answers
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Is R's apply family more than syntactic sugar?
...ntly different performance:
> fibo <- function(n) {
+ if ( n < 2 ) n
+ else fibo(n-1) + fibo(n-2)
+ }
> system.time(for(i in 0:26) fibo(i))
user system elapsed
7.48 0.00 7.52
> system.time(sapply(0:26, fibo))
user system elapsed
7.50 0.00 7.54
> s...
How to suppress warnings globally in an R Script
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235
You could use
options(warn=-1)
But note that turning off warning messages globally might no...
Configuring Vim for C++
...r project.
Class navigation: Taglist or Tagbar
Edit: Updated as of July 2013
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NSLog an object's memory address in overridden description method
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RVM is not working in ZSH
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275
Do you have this line in your ~/.zshrc?
[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME...
Add column with number of days between dates in DataFrame pandas
...etime
Out[11]:
A datetime64[ns]
B datetime64[ns]
dtype: object
In [12]: df['A'] - df['B']
Out[12]:
one -58 days
two -26 days
dtype: timedelta64[ns]
In [13]: df['C'] = df['A'] - df['B']
In [14]: df
Out[14]:
A B C
one 2014-01-01 2014-02-28 -58 days
two 2014-02...
Connection string using Windows Authentication
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Way to read first few lines for pandas dataframe
...kes a long time to read, and occasionally only want to use the first, say, 20 lines to get a sample of it (and prefer not to load the full thing and take the head of it).
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