23. Statistics: RPy2 from Sage

1. Last homework assignment
2. Questions

3. Lecture: http://flask.sagenb.org/home/pub/57/

wstein@sage:~$ sage -R

R version 2.10.1 (2009-12-14)
Copyright (C) 2009 The R Foundation for Statistical Computing
ISBN 3-900051-07-0

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> 
> 2 + 3
[1] 5
> 2 + 3
[1] 5
> c(1,2,4,8,9,10,10,10)
[1]  1  2  4  8  9 10 10 10
> v = c(1,2,4,8,9,10,10,10)
> 
> v+v
[1]  2  4  8 16 18 20 20 20
> c(v,v)
 [1]  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10
> c(v,v,v)
 [1]  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10
> c(v,v,v,v)
 [1]  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10  1
[26]  2  4  8  9 10 10 10
> c(v,v,v,v,v)
 [1]  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10  1
[26]  2  4  8  9 10 10 10  1  2  4  8  9 10 10 10
> pi
[1] 3.141593
> v = pi
> w = v + 1; w
[1] 4.141593
> w = c(v, 1); w
[1] 3.141593 1.000000
> w[1]
[1] 3.141593
> w[2]
[1] 1
> letters
 [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s"
[20] "t" "u" "v" "w" "x" "y" "z"
> sum( c(1,NA,2,3), na.rm=TRUE )
[1] 6
> sum( c(1,NA,2,3), na.rm=FALSE )
[1] NA