How to convert imported data from excel, with R pkg "readxl", to vectors/matrix in order to use them as 3-dimensions coordonnates?

library(rgl)
library(readxl)
library(plot3D)
library(plot3Drgl)

don<-read_excel("Classeur2.xlsx", col_names = TRUE, col_types = NULL, n_max = 24, guess_max = 24)

x0 = 0
y0 = 0
z0 = 0
arrows3D(x0, y0, z0, x1 = don[1,1], y1 = don[1,2], z1 = don[1,3], lwd = 2, d = 4, length = 0.5, main = "essai")
# Error in cbind(as.vector(x), as.vector(y), as.vector(z), 1) %*% plist$mat : 
#  nécessite des arguments numériques/complexes matrice/vecteur