Thread: mathematica help!

hi everyone,
i use mathematica for analysing data, i have a list {(v0,io),(v1,i1),(v2,i2)....(vn,in)} and i want plot dv/d(lnI). vs. i,
what i do to calcul dv/d(lnI)

How about this:

Code:

(* Create table of {{vn,in}} test values *)
mytable = Table[{n, n}, {n, 1, 10}]

(* switch the {v,i) to {log[i],v} *)
newtable = {N[Log[#[[2]]]], #[[1]]} & /@ mytable

(* calculate interpolation function of the list {log (i),v} *)
myfunction = Interpolation[newtable]

(* calculate the derivative dv/d log (i) *)

mydev[t_] = D[myfunction[t], t]
Plot[mydev[t], {t, 1, 10}]

i do what u say, and i want plot dv/d(lnI). vs. I,
what i do now boss