I get this error when include first column (name sex) as stated in above codes: Error in PCA(decathlon2.active, graph = FALSE) :
The following variables are not quantitative: Sex
Thanks for posting here on community! Just as a heads up, I've moved this to the general category as it's more of an R stats question and wanted to get more eyes on it here!
you need to tell PCA to exclude this variable or use it as supplementary or if you want it to be included in the analysis used a method that can handle a mix of quantitative and qualitative variables like FAMD