Reformat a correlation matrix in R to remove row names, column names, and cells in the top-right "half"

To input a correlation matrix for SEM in R, I need to reformat a matrix in three ways:

• Remove row names
• Remove column names
• Remove all cells in the top-right "half" of the matrix, above the diagonal 1 values

In other words, the matrix...

          EDU       CLASS       INCOME    AUTONOMY        COL5         ALT5         IIDM
EDU       1.00000000 -0.14591135  0.246463592  0.21938208 -0.09727587 -0.043862753  0.062896738
CLASS    -0.14591135  1.00000000 -0.048511437 -0.01469029  0.01663138  0.036140650 -0.010155653
INCOME    0.24646359 -0.04851144  1.000000000  0.13778603 -0.06969773 -0.051922861  0.009402784
AUTONOMY  0.21938208 -0.01469029  0.137786034  1.00000000 -0.25223015  0.023174980  0.073941520
COL5     -0.09727587  0.01663138 -0.069697725 -0.25223015  1.00000000 -0.300825028 -0.062978212
ALT5     -0.04386275  0.03614065 -0.051922861  0.02317498 -0.30082503  1.000000000  0.001553936
IIDM      0.06289674 -0.01015565  0.009402784  0.07394152 -0.06297821  0.001553936  1.000000000

... needs to become the text...

 1.00000000
-0.14591135  1.00000000
 0.24646359 -0.04851144  1.000000000
 0.21938208 -0.01469029  0.137786034  1.00000000
-0.09727587  0.01663138 -0.069697725 -0.25223015  1.00000000
-0.04386275  0.03614065 -0.051922861  0.02317498 -0.30082503  1.000000000
 0.06289674 -0.01015565  0.009402784  0.07394152 -0.06297821  0.001553936  1.000000000

... to be inputted line-by-line into the readMoments function, as shown below.

R.bd <- readMoments(names=c('EDU',
                            'CLASS',
                            'INCOME',
                            'AUTONOMY',
                            'COL5',
                            'ALT5',
                            'IIDM'))
 1.00000000
-0.14591135  1.00000000
 0.24646359 -0.04851144  1.000000000
 0.21938208 -0.01469029  0.137786034  1.00000000
-0.09727587  0.01663138 -0.069697725 -0.25223015  1.00000000
-0.04386275  0.03614065 -0.051922861  0.02317498 -0.30082503  1.000000000
 0.06289674 -0.01015565  0.009402784  0.07394152 -0.06297821  0.001553936  1.000000000

We are currently doing this manually by copying, deleting, and pasting. Any suggestions on how to go about writing a function to do this would be greatly appreciated.

Thanks, Jonathan

You can create the object R.bd directly. You don't need to input line by line.

Assuming, dat is the name of the object (data frame or matrix):

dat[upper.tri(dat)] <- 0 # replace all elements above the diagonal with 0
R.bd <- as.matrix(dat)  # transform to matrix (not necessary if it's a matrix)

That's it. You don't need to specify the names since they are already in the matrix object.