Correlation matrix correlations in R shown as "?" in the grid

Question

I want to create a correlation matrix given the "data1.new"-dataset. I know that ´NA´ values are represented by question marks. I have removed the NA values by using the "complete.obs".

data1.new<-data1[4:11]
summary(data1.new)
cor(data1.new, use = "complete.obs")
library(corrplot)
forcorrplot <- cor(data1.new)
corrplot(forcorrplot, method="number",shade.col=NA, tl.col="black", tl.srt=45)

My results are as follows:

Answer 1

The issue is that cor with complete.obs is not assigned to the object forcorrplot

library(corrplot)
data(mtcars)
mtcars[1:5, 2:5] <- NA
M <- cor(mtcars)
corrplot(M, method = 'number', shade.col=NA, tl.col="black", tl.srt=45)

and now check with

M <- cor(mtcars, use = "complete.obs")
corrplot(M, method = 'number', shade.col=NA, tl.col="black", tl.srt=45)