m0<-epxression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x)
params<-all.vars(m0) this reads all the params
from m0 so theta1,2 and 3 correct?
params<-params[-which(params=="x")] checks which params are
multiplied
by x?
np<-length(params)
for(i in 1:6){
esp<-get(sprintf("m%d",i-1)) what does get do?
sprinf
formats strings? so what is it doinf here?
assign(sprintf("m%d",i),D(esp,"x")) what doeas
assign so what in
sprintf doing and what does D do?
}
really really confused?
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Have you looked at the manual for any of these? ?get ?sprintf ?assign #and so on... ? Bazman76 wrote:> > m0<-epxression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x) > > params<-all.vars(m0) this reads all the > params from m0 so theta1,2 and 3 correct? > params<-params[-which(params=="x")] checks which params are > multiplied by x? > np<-length(params) > > for(i in 1:6){ > esp<-get(sprintf("m%d",i-1)) what does get do? sprinf > formats strings? so what is it doinf here? > assign(sprintf("m%d",i),D(esp,"x")) what doeas assign so what > in sprintf doing and what does D do? > } > > really really confused? >-- View this message in context: r.789695.n4.nabble.com/Confusing-piece-of-R-code-tp3656660p3656824.html Sent from the R help mailing list archive at Nabble.com.
The neat thing about R is that it's interpreted, so you can look for yourself. On Sat, Jul 9, 2011 at 3:46 PM, Bazman76 <h_a_patience at hotmail.com> wrote:> m0<-epxression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x) > > params<-all.vars(m0) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?this reads all the params > from m0 so theta1,2 and 3 correct?> m0<-expression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x) > params<-all.vars(m0) > params[1] "theta1" "theta2" "theta3" "x" So no, not just the thetas but also x> params<-params[-which(params=="x")] ? ? ?checks which params are multiplied > by x?> params<-params[-which(params=="x")] > params[1] "theta1" "theta2" "theta3" Nope, see that it takes out the params that are not equal to x. You could look at, for instance ?which to figure that out, and also ?"=="> np<-length(params) > > for(i in 1:6){ > esp<-get(sprintf("m%d",i-1)) ? ? ? ? ? ? ? ? ? ?what does get do? sprinf > formats strings? so what is it doinf here?Again, you can try it.> i <- 1 > sprintf("m%d",i-1)[1] "m0" So it's taking the value of i, and combining it with some other things to make a character name. get() will get the R object with that name and assign it to esp ?get will tell you that.> assign(sprintf("m%d",i),D(esp,"x")) ? ? ? ? ? ? what doeas assign so what in > sprintf doing and what does D do? > }Same thing in reverse. I'll leave this one as an exercise for the querent. Sarah> really really confused?Learning to try things and to read the help are the only cure. Sarah -- Sarah Goslee functionaldiversity.org
thanks sarah -- View this message in context: r.789695.n4.nabble.com/Confusing-piece-of-R-code-tp3656660p3656898.html Sent from the R help mailing list archive at Nabble.com.