[R] fraction with timelag

2011-03-24 Thread Patrick Hausmann
Dear r-help, I'm having this DF df - data.frame(id = 1:6, xout = c(1234, 2134, 234, 456, 324, 345), xin= c(NA, 34,67,87,34, NA)) and would like to calculate the fraction (xin_t / xout_t-1) The result should be: # NA, 2.76, 3.14, 37.18, 7.46, NA I am sure

Re: [R] fraction with timelag

2011-03-24 Thread Bill.Venables
] fraction with timelag Dear r-help, I'm having this DF df - data.frame(id = 1:6, xout = c(1234, 2134, 234, 456, 324, 345), xin= c(NA, 34,67,87,34, NA)) and would like to calculate the fraction (xin_t / xout_t-1) The result should be: # NA, 2.76, 3.14, 37.18, 7.46