Building a ROC producing function in R - r

Question

I want to make a function that accepts an xgboost model and the data (test set that I already got, called mydata[[2]]) and returns a ROC curve.
My first try was like this:
evaluate_model_plot = function(model,data) {
plt = roc(data[,1],predict(model, data[,-1]))
plot(plt, main = 'Test Set')
}
I get this error:
> evaluate_model_plot(myxgb, mydata[[2]])
Error in xgb.DMatrix(newdata, missing = missing) :
xgb.DMatrix does not support construction from list
I tried again:
evaluate_model_plot = function(model,data) {
dtest = xgb.DMatrix(data = data.matrix(data[,-1]),label=as.numeric(as.character(data[,1])))
plt = roc(dtest,predict(model, dtest))
plot(plt, main = 'Test Set')
}
Now the error is:
Error in unique.default(x, nmax = nmax) :
unique() applies only to vectors
I'm not sure how to fix this. The first error is not very clear to me since the data I'm providing is a data frame, it's saying that it doesn't accept a list, although the input is not a list..
Here is a sample from my test set:
> dput(data[[2]][1:15,1:5])
structure(list(CR = structure(c(1L, 1L, 1L, 1L, 2L, 1L, 1L, 1L,
1L, 2L, 2L, 1L, 1L, 1L, 1L), levels = c("0", "1"), class = "factor"),
CD4.T.cells = c(0.0410284948786532, -0.0366277340916379,
-0.0349008907108641, -0.062499826731091, -0.206241592996545,
-0.0874700869552125, -0.182120904486964, -0.171941115538424,
-0.101887370292612, -0.0471260521659922, 0.00336508376392719,
-0.0558977705951249, -0.0346269111530533, 0.0405376992753275,
-0.116824556352525), CD8.T.cells = c(-0.0372301980787381,
-0.0550538743643369, -0.157003425700701, -0.280984614146961,
-0.245432535063266, -0.147192190940429, -0.244633652045209,
-0.213892169574032, -0.301036923607255, -0.427604924497491,
-0.371628492024595, -0.0166106304573527, -0.200413064153971,
-0.276715360733834, -0.13198989690999), T.helpers = c(0.186447606591857,
0.0686746776877563, -0.0662055287009653, -0.0969110962088053,
-0.176807066557773, -0.079679981476819, -0.0642576894506894,
-0.0543810984331623, -0.0741755574175595, -0.0131228323048211,
-0.214234307929943, -0.0137492004706794, -0.000982317887326278,
-0.126128005295858, -0.177662982037535), NK.cells = c(-0.0172673823614314,
-0.0518877213975413, -0.129207379606117, -0.174457678991973,
-0.103184559349521, -0.0415572732935339, -0.100644327844509,
-0.124636632740142, -0.131184498665394, -0.181979331198521,
0.0352080568467581, -0.00354359170704435, -0.0820137078499403,
-0.167969284367181, 0.132078267822988)), row.names = c("Pt101",
"Pt18", "Pt2", "Pt3", "Pt48", "Pt59", "Pt67", "Pt82", "Pt98",
"EA595647", "EA632133", "EA632149", "EA632171", "EA639018", "G109543_RCCBMS-00114-T_v1_RNA_OnPrem"
), class = "data.frame")