[R] Extract lags from a formula

Hi folks! How do I extract lags from a formula? An example: mod.eq-formula(x~lag(x,-1)+lag(x,-2)) mod.eq x ~ lag(x, -1) + lag(x, -2) mod.eq[1] ~() mod.eq[2] x() mod.eq[3] lag(x, -1) + lag(x, -2)() I'm trying to extract the lags into a vector that would be simply [1,2]. How

Re: [R] Extract lags from a formula

On Fri, May 2, 2008 at 1:35 PM, Kerpel, John [EMAIL PROTECTED] wrote: Hi folks! How do I extract lags from a formula? An example: mod.eq-formula(x~lag(x,-1)+lag(x,-2)) mod.eq x ~ lag(x, -1) + lag(x, -2) mod.eq[1] ~() mod.eq[2] x() mod.eq[3] lag(x, -1) +

Re: [R] Extract lags from a formula

If x is a zoo object note that zoo (and therefore dyn) allows the more compact form lag(x, -(1:2)) so if we write: mod.eq - x ~ lag(x, -(1:2)) then mod.eq[[3]][[3]] is the vector -(1:2) or if you like you can define Lag - function(x, k) lag(x, -k) in which case you can write it: mod.eq - x ~