search for: deivative

Full_Name: Michael J. Lew Version: R version 2.9.1 (2009-06-26) OS: OS X Submission from: (NULL) (210.49.195.149) The default function power.t.test gives inaccurate values, particularly with large sig.level. There are two reasons for me to propose that power.t.test is inaccurate: 1. When sig.level approaches 1, so should the power. However,

...erivative of a polynomial in R i<- -10:10 x<-i*i*i+3*i*i+2 fun_spline<-splinefun(i,x) plot(x,type="l") lines(x,fx_spline(x, deriv=1), col='green') lines(x,fx_spline(x, deriv=2), col='green') Now when I plot 3*i*i + 6*i and 6*i + 6 the plot was not same for first deivative. where as the 2nd derivative was same Is this a correct method for getting derivative. where am I doing wrong as first derivative? lines(x,fx_spline(x, deriv=1), col='green') is not correct. amar -- Amar Kumar Nandan