Shapiro test: is.numeric (x) is not TRUE

Question

I have problems with the shapiro.test function to check normality. I keep getting the error

is.numeric (x) is not TRUE

I use the following dataset (name: Abund2014layer):

Abundance
0.91567
0.01256
...
0.85605

which goes on for 75 rows.

I implement it as follows:

shapiro.test(Abund2014layer)

But I keep getting the error. The input should be a numeric vector of data values, I don't see where it goes wrong.

Solution

Is the data you are providing to shapiro.test a vector? If it is a data.frame then it will return this error. Try using shapiro.test(Abund2014layer$Abundance)

If you still get the error, you can see what class your vector is by using the class(Abund2014layer$Abundance) function. If it is not numeric, you can transform it and perform the Shapiro test in one line as follows;

shapiro.test( as.numeric( Abund2014layer$Abundance ) )