On Wed, 16 Nov 2005, Vivien W. Chen wrote: > Hi! > > I am a beginner of R. I am trying to calculate integrate and draw a > graph of the output, but just kept on getting error messages. I list my > program and error message below. Please help. Many Thanks! > > ======================= > + > a<--11 >> b<-0.1 >> c<-0.012 >> x<-0:110
This is harmless but suspicious -- this x is completely unrelated to the x in integrand() >> t<-0:15 >> integrand<-function(x) {exp(-exp(a-c*t)*(exp(b*x)-exp(c*x))/(b-c))} The problem is that x is a vector of whatever length integrate() decides to pass, but t is a vector of length 16. This mismatch of lengths is going to cause a problem. >> cal<-integrate(integrand,0,Inf) > Error in integrate(integrand, 0, Inf) : evaluation of function gave a result > of wrong length > In addition: Warning message: > longer object length > is not a multiple of shorter object length in: -exp(a - c * t) * > (exp(b * x) - exp(c * x)) >> plot(cal~t, xlab="Time", ylab="Pop at t") > Error in model.frame(formula, rownames, variables, varnames, extras, > extranames, : > invalid variable type > =========================== > > - Vivien Chen - > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > Thomas Lumley Assoc. Professor, Biostatistics [EMAIL PROTECTED] University of Washington, Seattle ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html