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Topic: Help on PCA: Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric (Read 92 times) previous topic - next topic

Help on PCA: Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric

Hi,
Any body knows how to solve this R PCA problem? I`ve try many times, I still don`t know the reason. I hope somebody could help me
When I type:
> dtp<-prcomp(tdt,retx= TRUE,center= TRUE,scale= TRUE)
Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric

Thanks in advance for all your help.

 

Re: Help on PCA: Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric

Reply #1
Hello,
One of your columns contains non-numeric information. This might be because your data frame (tdt) has a column specifying the treatment. Here is an example with the iris data set which has "Species" in column 5.

data("iris")
pca <- prcomp(iris)  # Fails with "Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric"
pca <- prcomp(iris[1:4])  # Success

Hope this helps.