Michaelis-Menten model

DESCRIPTION:

This selfStart model evaluates the Michaelis-Menten model and its gradient. It has an initial attribute that will evaluate initial estimates of the parameters Vm and K

USAGE:

SSmicmen(input, Vm, K) 

REQUIRED ARGUMENTS:

input
a numeric vector of values at which to evaluate the model.
Vm
a numeric parameter representing the maximum value of the response.
K
a numeric parameter representing the input value at which half the maximum response is attained. In the field of enzyme kinetics this is called the Michaelis parameter.

VALUE:

a numeric vector of the same length as input. It is the value of the expression Vm*input/(K+input). If both the arguments Vm and K are names of objects, the gradient matrix with respect to these names is attached as an attribute named gradient.

SEE ALSO:

,

EXAMPLES:

PurTrt <- Puromycin[ Puromycin$state == "treated", ] 
SSmicmen( PurTrt$conc, 200, 0.05 )  # response only 
Vm <- 200 
K <- 0.05 
SSmicmen( PurTrt$conc, Vm, K ) # response and gradient