search for: euqations

I used the command below, but R gives me the error message--syntax error. can anyone see the mistakes I made? optimize(function(x,y) + ((327.727-(1-0.114^10)*y*(1-x)/x/(1-x^y))+(9517.336-327.727 *(1+(1-x)*(1+y)/x-327.727)))^2 + interval=c(0,1)) At the same time, I use nlm() but R gives me the code $code [1] 3 function(vals) { x <- vals[1] y <- vals[2]

Dear R-users Problem: Given the following system of ordinary differential euqations dM/dt = (-n)*M-h*M dS/dt = n*M-h*S+u*R dA/dt = h*S-q*A dI/dt = q*A-p*I dJ/dt = h*M-v*J dR/dt=p*I+v*J-u*R where M,S,A,I,J,R are state variables and n,h,u,q,p,v parameters. I'm able to calculate the likelihood value based on the solutions M,S,A,I,J,R of the ODE's given the data, but witho...

Hi I have measured the UV absorbance (abs) of 10 solutions of a substance at known concentrations (conc) and have used a linear model to plot a calibration graph with confidence limits. I now want to predict the concentration of solutions with UV absorbance results given in the new.abs data.frame, however predict.lm only appears to work for new "conc" variables not new "abs"