Convert squared genomic relationship matrix into GCTA format

Hi all,

I have a GRM that we have used in previous analyses, and now would like to use this same GRM for chromosome partitioning in GCTA.

Is there a way of using external GRMs that have not been calculated by GCTA?

Or, alternatively, is there a reliable package in R that converts my GRM into the .bin format?

I heard of "OmicKriging" and "gap", but both give me the following error: "Error in file(BinFileName, "wb") : invalid 'description' argument"



Grateful for any advice!