Parodi, Pietro
2011-Apr-21 15:05 UTC
[R] Converting from density to cumulative distribution
Hello I'm trying to do the following vector operation: given vector x = c(x1,x2,x3,x4...xn), produce vector y c(x1,x1+x2,x1+x2+x3,...x1+...+xn). E.g., from x = c(1,3,2,2,5), produce y = c(1,4,6,8,13). The underlying problem is finding the cumulative distribution function given the empirical density distribution function. I have done some research on this but the only relevant thing I've found is the function "integrate", which however gives me the sum of the whole vector not the step-wise sum. Thanks for your help Pietro ______________________________________________________________________ For information pertaining to Willis' email confidentiality and monitoring policy, usage restrictions, or for specific company registration and regulatory status information, please visit http://www.willis.com/email_trailer.aspx We are now able to offer our clients an encrypted email capability for secure communication purposes. If you wish to take advantage of this service or learn more about it, please let me know or contact your Client Advocate for full details. ~W67897 ______________________________________________________________________ [[alternative HTML version deleted]]
?cumsum> x = c(1,3,2,2,5) > cumsum(x)[1] 1 4 6 8 13>On Thu, Apr 21, 2011 at 11:05 AM, Parodi, Pietro <Pietro.Parodi at willis.com> wrote:> > Hello > > I'm trying to do the following vector operation: > > given vector x = c(x1,x2,x3,x4...xn), ?produce vector y > c(x1,x1+x2,x1+x2+x3,...x1+...+xn). > > E.g., ?from x = c(1,3,2,2,5), produce y = c(1,4,6,8,13). > > The underlying problem is finding the cumulative distribution function > given the empirical density distribution function. > > I have done some research on this but the only relevant thing I've found > is the function "integrate", which however gives me the sum of the whole > vector not the step-wise sum. > > Thanks for your help > > Pietro > > > ______________________________________________________________________ > > For information pertaining to Willis' email confidentiality and monitoring policy, usage restrictions, or for specific company registration and regulatory status information, please visit http://www.willis.com/email_trailer.aspx > > We are now able to offer our clients an encrypted email capability for secure communication purposes. If you wish to take advantage of this service or learn more about it, please let me know or contact your Client Advocate for full details. ~W67897 > ______________________________________________________________________ > > ? ? ? ?[[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- Jim Holtman Data Munger Guru What is the problem that you are trying to solve?