[R] inverse cumsum

[(Ted Harding)]

On 18-Jun-08 10:17:09, Alfredo Alessandrini wrote:
> I've a matrix like this:
> 
> 1985     1.38     1.27     1.84     2.10     0.59     3.47
> 1986     1.05     1.13     1.21     1.54     0.21     2.14
> 1987     1.33     1.21     1.77     1.44     0.27     2.85
> 1988     1.86     1.06     2.33     2.14     0.55     1.40
> 1989     2.10     0.65     2.74     2.43     1.19     1.45
> 1990     1.55     0.00     1.59     1.94     0.99     2.14
> 1991     0.92     0.72     0.50     1.29     0.54     1.22
> 1992     2.15     1.28     1.23     2.26     1.22     3.17
> 1993     1.50     0.87     1.68     1.97     0.83     2.55
> 1994     0.69     0.00     0.76     1.89     0.60     0.87
> 1995     1.13     1.04     1.19     1.52     1.13     1.78
> 
> Can I utilise a cumsum inverse? from 1995 to 1985?
> 
> Thank you,
> Alfredo

Try on the lines of:

  cumsum(c(1,2,3,4,5))
# [1]  1  3  6 10 15
  cumsum(rev(c(1,2,3,4,5)))
# [1]  5  9 12 14 15

Hoping this helps,
Ted.

--------------------------------------------------------------------
E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 18-Jun-08                                       Time: 11:50:40
------------------------------ XFMail ------------------------------