I'm trying to use the user-created multinomRob to make some models for my data. While documentation for that function is great and I think I'm using it correctly, I'm getting the following error when I try to use my dataframes.

data <- read.csv("data.csv", header=FALSE)

subj1 <- data.frame(radius=data$V3[9:11], x1=data$V4[9:11], x2=data$V5[9:11], x3=data$V6[9:11])

> subj1

radius x1 x2 x3

1 436.61 1.00000 0.000000 0.000000

2 735.27 1.00000 0.000000 0.000000

3 901.73 0.96081 0.053223 -0.055439

co1 <- multinomRob(model=list(radius ~ x1 + x2 + x3), subj1, starting.values=NULL, equality=list(radius ~ x1 + x2 + x3 + 0))

Error in dimnames(XYdata$Y) <- list(NULL, XYdata$ynames) :

length of 'dimnames' [2] not equal to array extent

I'm coming from a background of several years with MATLAB so this particular message means nothing to me. My prior experience with R is limited to using lm() but I converted for this particular application because I was told it was quite good and handling nonlinear regression. But looking at what I have, I see an array where I have the same number of labels as columns so I have no idea what the issue is. Thank you in advance for your assistance!