[R] Fitting a gaussian distribution to a plot

Samantha Warnes
Wed, 20 Feb 2013 23:33:01 -0000

I have a peak I would like to fit with a gaussian distribution, and am having
difficulties. First of all I am having difficulties getting R to except my
function input, and additionally I am having trouble plotting the non linear
model on my scatterplot of data (the peak). Here is my log:

> small <-
c(507680,507670,508832,510184,511272,513380,515828,519160,525046,534046,547982,567124,590208,614506,637876,656846,669054,672976,668800,656070,637136,614342,590970,570752,554480,542882,535630,531276,528682,527682,527020,526834,526802,526860)
> plot(small)
> mean(small)
[1] 563996.7
> sd(small)
[1] 55996.21

> x <-c(0:35)
> x <-as.numeric(x)
> f <-
((1/(55996.21)*sqrt(2*pi)))*exp^(-((x-563996.7)^2)/(2*(55996.21^2)))



Error in exp^(-((x - 563996.7)^2)/(2 * (55996.21^2))) :
 non-numeric argument to binary operator



>From this point, to fit a non-linear model so I type nlm(f,507680)? I have
tried reading up on this and looking for additional information on the internet
but I am truly stuck. Thank you in advance!
Samantha